Terms of Service

MailCull (“the service”) helps you clean email lists and check individual addresses through two user-facing workflows: Verify List for uploaded CSV lists, and Verify Email for single-address checks. The service provides statuses, scores, filtering, exports, and account-based history. A public API is available on paid plans and is described in section 9.

The service is operated by the MailCull team, based in Maharashtra, India (“we”, “us”, “MailCull”). By creating an account or using the service you accept these terms.

You must be at least 16 years old to create an account and use the service. By creating an account you confirm that you can lawfully enter into these terms.

• You are responsible for keeping your account credentials secure and for all activity that happens through your account.
• You must provide accurate registration details and keep your email address current so you can receive account, billing, and security messages.
• One account per person is the expected use. Sharing a single account across an organisation is allowed if a single billing party is responsible for activity on the account.

You may use the service only for lawful business or operational purposes. You may not use the service to overload, disrupt, probe, scrape, reverse engineer, or abuse the platform or other users.

• Do not upload malicious, misleading, or intentionally malformed files.
• Do not try to bypass limits, quotas, export restrictions, rate limits, or account protections.
• Do not attempt to access accounts, sessions, API keys, or data that do not belong to you.
• Do not resell raw service output as a stand-alone product, or repackage it in a way that misrepresents the source of the data.

3.1 Lawful basis and anti-spam compliance

You represent and warrant, every time you use the service, that:

• You have a lawful basis (consent, contract, legitimate interest, or another basis recognised by applicable data-protection law, including GDPR Article 6, the UK GDPR, the Indian Digital Personal Data Protection Act 2023, the CCPA and equivalent US state laws, and any other applicable framework) for processing each email address you upload, single-check, or query through the API.
• The addresses were obtained lawfully and have not been derived from a data-breach corpus, scraped from a website in violation of that website’s terms, or purchased from a third-party lead vendor of unknown provenance.
• Any communication you subsequently send to addresses we mark deliverable, risky, undeliverable, or unknown complies with applicable anti-spam and unsolicited-communication law, including but not limited to CAN-SPAM (US), CASL (Canada), GDPR + PECR (EU/UK), Australia’s Spam Act, and the local laws of any jurisdiction in which the recipient is located.
• You are not using the service to send unsolicited bulk commercial messages in violation of those laws.

You retain sole responsibility for compliance. MailCull does not endorse spam and will terminate accounts found to be sending unsolicited bulk commercial messages, with no refund.

3.2 High-risk uses prohibited

You may not use the service, directly or indirectly, for any of the following:

• Harassment, stalking, doxxing, threats, or coordinated targeting of individuals.
• Identifying, profiling, or contacting children, or processing data of individuals known or reasonably suspected to be under 16.
• Validating addresses obtained from a data breach, leaked credential dump, or any other unlawful source.
• Political microtargeting in jurisdictions where it is regulated.
• Phishing, impersonation, fraud, or any messages designed to deceive recipients about their sender or purpose.
• Building, training, or enriching a marketing list of people who have not given you a lawful basis to contact them.
• Building or training a competing email-validation service from MailCull’s outputs, methodology, or evidence-chain format.

3.3 Sanctions and export controls

You may not access or use the service if you are located in, ordinarily resident in, or a national of any country subject to comprehensive US, UK, or EU sanctions, or if you appear on the US OFAC Specially Designated Nationals list, the EU consolidated sanctions list, the UK OFSI consolidated list, or any equivalent denied-persons or denied-entities list.

3.4 Enforcement

Violation of any provision in this section is grounds for immediate suspension or termination under section 12, without refund. We may also disclose information about the account and the activity to relevant authorities where required by law (see Privacy Policy).

You are responsible for the content you upload and for making sure you have the right to use the email data you submit. If you upload a CSV file, you are responsible for its contents, structure, and lawful use, including any obligations under data-protection law that apply to the people whose addresses appear in the file.

You represent and warrant that you have the lawful basis described in section 3.1 to process each address, that the addresses were obtained lawfully and not from a breach corpus or unlawful source, and that on reasonable request (for example, in response to a third-party complaint or regulatory inquiry) you will provide MailCull with evidence of that lawful basis.

As between you and MailCull, you retain all rights to the lists, results, and exports tied to your account. You grant us the limited, non-exclusive licence needed to process that data to operate the service for you and to comply with our legal obligations. We process this data on your behalf to operate the service. The Privacy Policy explains how we handle that processing.

If you require formal data-processing terms (a Data Processing Addendum or equivalent) to satisfy your own compliance obligations, email [email protected] and we will work with you on terms that fit your situation.

The service gives you operational guidance, not a promise that a mailbox will always accept mail or that an address will always perform well. Statuses (deliverable, risky, undeliverable, unknown) and confidence scores are decision aids. You should use your own judgment before relying on any result in a higher-risk workflow.

Validation accuracy is influenced by factors outside our control, including but not limited to: recipient-server configuration changes, catch-all and greylisting policies, server-side spam filtering, sender reputation, content filtering, blacklist listings, and changes made by mailbox providers (Microsoft, Google, Yahoo, and others) to their probe-acceptance behaviour. The service queries publicly available DNS, MX, and SMTP signals at the time of the validation run; if those signals change between the validation and the time you send mail, the result may no longer reflect the recipient mailbox state.

The four-status taxonomy is intentionally broader than a binary valid/invalid: the risky and unknown statuses are how MailCull communicates that the underlying signals are inconclusive. Treat those statuses accordingly and do not promote them to deliverable in your own pipeline.

We make no representation or warranty that any specific accuracy percentage will be achieved on any given list. Independent third-party benchmarks of email-validation services typically place industry-wide real-world accuracy on mixed lists in the 90–97% range, and our results are subject to the same factors. We do not publish a marketing accuracy figure on the homepage on purpose: where you need higher-stakes assurance, sample a portion of the list manually before sending, or contact [email protected].

Mailbox-level (deep-scan) results may appear in two phases: an initial signal followed by a refined signal as enrichment finishes. We make a reasonable effort to keep enrichment fast, but we do not commit to a specific completion time for any individual address.

AI read (AI Analyst). On request, the service can generate an optional plain-English “AI read” of a result (a summary, a suggested next step, and a confidence read) using a third-party AI model (OpenAI). The AI read is informational and advisory only. It explains the deterministic verdict; it does not produce or change it, and the deterministic status remains authoritative. AI-generated text may occasionally be incomplete or imperfect, is provided without warranty, and should not be treated as the result itself. Availability and monthly limits of the AI read depend on your plan and may change with notice. Data sent to the AI provider when you use this feature is described in our Privacy Policy.

MailCull is offered on a Free plan and a paid Pro plan. The features of each plan are summarised on the pricing page, and the current per-plan limits are shown inside the product on the Account page. We may change plan limits, features, and pricing at our discretion, subject to the notice rules below.

Free plan. 500 validation credits per month. Includes the full deep SMTP probe (mailbox-level scan with catch-all detection) on every check, the same scan engine Pro uses, plus 25 optional AI reads per month. CSV uploads and single-email checks are available. Per-upload row limits and the maximum number of active jobs are smaller than Pro and are shown in the product. No API access. No MCP access for AI agents.

Pro plan. 100,000 validation credits per month for $9 per month, flat. Same deep SMTP probe scan engine as Free, with the larger credit pool plus 500 AI reads per month, REST API access (with webhooks for async jobs), and MCP access so AI assistants such as Claude and Cursor can verify emails, queue jobs, and check credits on your behalf. Larger per-upload row limits and a higher cap on concurrent active jobs apply; the exact numbers are shown in the product and may be adjusted with notice.

• The Pro plan is sold as a recurring monthly subscription that renews automatically until cancelled.
• Pricing displayed on the pricing page at the time of your initial purchase governs your current billing period. Pricing for future renewal periods is subject to change. We will give existing paying customers at least 30 days’ notice by email to the address on the account before a price change takes effect; the next renewal at or after the notice period applies the new price.
• Each renewal charges the payment method on file for the next billing period at the price then in effect for your account. The renewal charge is final once processed; see section 8 for refund rules.
• You can cancel at any time through the Paddle customer portal (Account → Manage billing) or by emailing [email protected]. Cancellation takes effect at the end of the current billing period; you keep paid access until the period ends.
• Cancellation is your responsibility to confirm. After cancelling, verify that the Account page shows “Pro, cancels [date]” and keep the email confirmation Paddle sends. Cancellations apply to the NEXT renewal; they do not retroactively reverse a charge that has already processed.
• If a renewal charge fails, the account enters a recovery state. Pro access continues during recovery while we and the payment provider attempt to collect.
• Account deletion is intentionally blocked while a Pro subscription is active, in trial, paused, in recovery, or cancelled but not yet expired. Cancel and wait for the period to end, then the account becomes deletable.

All payments for the Pro plan are processed by Paddle (Paddle.com Market Ltd. and its affiliates, including Paddle.com Inc. for US-billed customers). Paddle acts as the Merchant of Record for these transactions, which means:

• Your invoice and receipt are issued by Paddle on our behalf.
• Paddle calculates, collects, and remits applicable VAT, GST, and sales taxes based on your billing location.
• Currency conversion, fraud screening, and chargeback handling are performed by Paddle.
• Your payment-method details are stored and processed by Paddle, not by MailCull. We never see or store full card numbers.

Pricing displayed on the site is exclusive of taxes unless explicitly noted. The total charged at checkout will include any applicable taxes determined by Paddle.

You can update your payment method, view invoices, and manage subscription renewal in the Paddle customer portal, reachable from the Account page. Paddle’s own terms and privacy policy apply to your use of that portal in addition to ours.

You may cancel your Pro subscription at any time through the Paddle customer portal (Account → Manage billing) or by emailing [email protected]. After cancellation, Pro features remain available until the end of the current billing period, and the account drops to Free automatically when the period ends. Cancellation alone does not entitle you to a refund of the current billing period; refund eligibility is governed by 8.1–8.5 below.

8.1 Bounce-rate refund (the “30-day money-back”)

On the FIRST paid period of an account only, if the real-world hard-bounce rate against addresses MailCull marked deliverable exceeds 3% based on a bounce report from your sending email service provider, you may request a full refund of that first paid period within 30 calendar days of the validation run.

To qualify, the request must include all of the following:

• The MailCull job ID of the validation run in question.
• A bounce report exported from a recognised email service provider (examples: Smartlead, Instantly, lemlist, Mailchimp, SendGrid, Klaviyo, Brevo, Postmark) covering at least 500 sent addresses that we marked deliverable.
• Hard-bounce events only. Soft bounces, suppression-list rejections, complaint events, and authentication-related rejections (SPF, DKIM, DMARC) are excluded from the rate calculation because they are not failures of address validation.
• Sends made within 30 days of the validation run, so the bounce signal reflects the addresses we validated rather than addresses that decayed afterwards.

Email [email protected] with the report attached. We respond within five business days. Approved refunds are initiated within two business days of approval and processed by Paddle, typically appearing on the original payment method within 5 to 10 business days from initiation.

The bounce-rate refund is available once per customer across all accounts. Subsequent disputes about validation accuracy are handled under section 8.4.

8.2 Renewals are NOT covered by 8.1

The 30-day money-back applies only to the first paid period of an account. Renewal charges are not covered.

If you intended to cancel before a renewal but the cancellation was not recorded (for example, an attempted cancellation in the Paddle portal that did not complete, a cancellation made after the renewal charge processed, or a forgotten cancellation), the renewal charge is final and not refundable. As stated in section 6, after cancelling you must verify the Account page shows the cancelled state and retain the Paddle confirmation email. We are not able to retroactively reverse a renewal charge based solely on a customer’s statement that they intended to cancel earlier.

8.3 Abuse safeguards (refunds may be declined)

We reserve the right to decline a refund request, including a bounce-rate refund under 8.1, where the pattern of use indicates the request is being made primarily to obtain free use of the service rather than as a good-faith dispute about quality. Examples include but are not limited to:

• More than 50% of the monthly validation credit allowance for the period consumed before the refund request.
• Bulk validation runs (more than 10,000 validations in a 24-hour window) immediately followed by a refund request.
• Repeat refund requests across multiple accounts opened by the same customer or organisation.
• API-key activity inconsistent with a good-faith evaluation, including automated bulk-scan patterns that suggest the validation run was completed before the refund window was considered.
• Refund requests where the claimed bounce rate is not corroborated by the bounce report (for example, a soft-bounce-heavy report being submitted as a hard-bounce claim).

Where we decline a refund on these grounds we will state the reason in writing. This subsection does not affect statutory rights you may have under cooling-off laws (see 8.5).

8.4 Discretionary refunds

Outside section 8.1, refunds are at our discretion and are usually only granted for clear billing errors, duplicate charges, or service failures attributable to us. Email [email protected] with your account email and the reason for the request.

8.5 Cooling-off (statutory)

If you are based in a jurisdiction with a statutory cooling-off period (such as the EU/UK 14-day right of withdrawal) and you have not substantially used the service in that period, you may exercise that statutory right within 14 days of your initial purchase. Statutory rights apply in addition to the rules above and are not waived or limited by them.

8.6 Mid-period cancellation

Pro-rata refunds for the unused portion of a billing period are not offered. Cancelling stops the next renewal but does not refund the current period, except where 8.1 or 8.5 applies.

Pro accounts can use the public API to integrate MailCull with their own systems. API use is subject to these terms in addition to the rules below.

• API keys are personal credentials. Do not share them publicly, do not commit them to source control, and rotate them if you suspect a leak.
• API requests are subject to per-minute rate limits (currently 300 requests per minute per API key, shared across the REST API and MCP server) and to your monthly validation-unit budget. Exceeding either causes requests to be rejected with a 429 or 402 response until limits reset.
• Mutating endpoints require an Idempotency-Key header so retries do not double-charge your budget. The full requirement is documented at /api/v1/docs.
• Programmatic abuse, including bypassing rate limits, key-rotation circumvention, or scraping the API surface for purposes outside normal product use, is prohibited and may lead to immediate revocation of all keys on the account.

Operational files are not stored forever. Uploaded source CSVs are normally removed within a couple of days after the run completes. Generated export files are normally kept for about a week so you can re-download them, after which they are pruned.

Your saved list history and Verify Email history are not pruned automatically; they remain in the product until you delete them. A completed list with no extractable email addresses may not offer export actions because there is nothing to download.

Concrete current retention windows are described in the Privacy Policy and may be adjusted as the product evolves. Material reductions in retention will be announced before they take effect.

The service may change over time, including limits, scoring behaviour, export behaviour, retention periods, available features, and the API surface. We will give reasonable notice for changes that affect paid plan entitlements. Continued use after updates means you accept the revised service terms.

We may limit, suspend, or terminate access to the service if an account is used in a way that creates risk, violates these terms, threatens service stability, or is non-paying for an extended period after recovery has been attempted. Where reasonably possible we will give notice and an opportunity to remedy the issue first.

You can terminate your account at any time by following the deletion instructions in the Account page, subject to the active-billing rule in section 6.

We aim to keep the service available and accurate, but we do not guarantee a specific uptime or that every result will be correct for every address at every moment. The service is provided on an “as is” and “as available” basis, without warranties of any kind, whether express or implied, to the maximum extent permitted by applicable law.

In particular, MailCull does not warrant that any specific message will be delivered, opened, or engaged with based on the result returned by the service. Email reputation, recipient mailbox behaviour, and provider rules are outside our control.

To the maximum extent permitted by applicable law, neither MailCull nor its operators will be liable for indirect, incidental, special, consequential, or punitive damages, or for lost profits, revenue, goodwill, sender reputation, or data, arising out of or related to your use of the service, even if we have been advised of the possibility of such damages.

Our total cumulative liability for any claim arising out of or related to these terms or the service is limited to the greater of the amount you paid us for the Pro plan in the twelve months before the event giving rise to the claim, or USD 100. Nothing in these terms excludes any liability that cannot lawfully be excluded.

We are not liable for failure or delay in performance to the extent caused by circumstances outside our reasonable control, including: natural disasters, pandemics, acts of war or terrorism, government action, infrastructure-provider failures (including failures at Hetzner, Paddle, Amazon Web Services, or any DNS or BGP-level provider), denial-of-service attacks, internet-wide outages, or labour disputes.

Where a force-majeure event substantially prevents us from delivering the service for more than 30 consecutive days, either party may terminate the affected subscription, and we will refund the unused portion of any prepaid amount on a pro-rata basis. This is the only circumstance in which a pro-rata refund is offered, notwithstanding section 8.6.

Features marked “beta”, “preview”, “early access”, or “coming soon” (including, at the time of these terms, the MCP server) are made available on an as-is basis without warranty of any kind. We may change, remove, or revoke access to beta features at any time without notice. Beta-feature outages or removal are not eligible for refunds under section 8 and do not amount to a service failure under section 8.4.

17.1 Indemnification by you

You will indemnify, defend, and hold harmless MailCull, its operators, affiliates, and personnel from and against any third-party claim, loss, damage, fine, regulatory penalty, settlement amount, and reasonable legal cost (including attorneys’ fees) arising out of or related to:

• Any address you uploaded, single-checked, or queried through the API, including the lawful basis (or absence of lawful basis) under which you obtained that address.
• Any communication you sent to addresses we marked deliverable, risky, undeliverable, or unknown, including without limitation claims for spam, unwanted contact, harassment, fraud, or violation of CAN-SPAM, CASL, GDPR, PECR, the DPDP Act, or any equivalent law.
• Any breach by you of section 3 (Acceptable use) or section 4 (Your data and upload responsibility), or of the warranties given in those sections.
• Any tort or regulatory claim brought by a person whose address appears in your upload, where the basis of the claim is connected with your use of the service.

We will give you reasonable notice of any claim covered by this section, allow you to control the defence (with counsel reasonably satisfactory to us), and reasonably cooperate at your expense.

17.2 Indemnification by us

To the extent permitted by applicable law, we will defend you against a third-party claim that the service, as provided by us and used by you in accordance with these terms, infringes that third party’s intellectual-property rights, and we will pay damages and reasonable legal costs awarded in such a claim or agreed in settlement (subject to the limitation in section 14). This obligation does not apply to claims arising from your data, your modifications, your combination of the service with other products, or your continued use of the service after we have notified you that a particular use should stop.

All intellectual property in the service (including the software, brand, methodology, the four-status taxonomy (deliverable, risky, undeliverable, unknown), the evidence-chain output format, the documentation, the visual design system, and any related trademarks) is owned by MailCull or its licensors. You receive a limited, non-exclusive, non-transferable, revocable licence to use the service for its intended purpose during your subscription. Nothing in these terms transfers any ownership of MailCull’s intellectual property to you.

You retain ownership of your own data, including your uploaded lists and the validation results tied to your account (see section 4). You grant us the limited licence needed to process that data to operate the service for you. We may use de-identified, aggregated metadata about service usage (such as job counts, status distributions, latency percentiles) for product improvement, capacity planning, and accuracy benchmarking, but we will not use the email addresses or list contents for any purpose other than providing the service.

Feedback you voluntarily provide to us about the service (suggestions, feature requests, bug reports) may be used by us without obligation to you, except where the feedback contains your own confidential information that you have asked us in writing not to use.

For legal notices to MailCull, email [email protected]. For privacy-specific notices, also copy [email protected]. We will give you legal notices by email to the address registered on your account, or through the product. You are responsible for keeping your account email current. A notice from us is deemed given on the day it is sent unless we receive a delivery-failure (bounce) signal.

We may assign these terms and our rights and obligations under them to a successor in connection with a merger, acquisition, reorganisation, sale of substantially all assets, or other corporate restructure. We will notify customers of an assignment by email at least 30 days in advance unless the transaction is confidential under securities or contract law, in which case we will notify as soon as legally permitted.

You may not assign these terms or any rights under them without our prior written consent. Any attempted assignment in breach of this section is void.

The following sections survive termination, cancellation, or expiry of these terms or any subscription: section 4 (Your data and upload responsibility), section 5 (Validation results, scores, and accuracy), section 8 (Refunds and cancellations, with respect to amounts already paid and refund-eligibility outcomes), section 13 (Service availability and disclaimers), section 14 (Limitation of liability), section 15 (Force majeure, with respect to events that occurred during the term), section 17 (Indemnification, with respect to claims accrued during the term), section 18 (Intellectual property), section 22 (Governing law and disputes), and any other provision that by its nature is intended to survive.

These terms are governed by the laws of the State of Maharashtra, India, without regard to its conflict-of-laws rules. The courts of the State of Maharashtra, India have exclusive jurisdiction to settle any dispute arising out of or in connection with these terms or the service, except where mandatory consumer-protection law gives you the right to bring proceedings in your country of residence.

If any provision of these terms is held unenforceable, the rest of the terms remain in effect.

If you have questions about these terms, contact [email protected]. For privacy-specific requests, see the contact details in the Privacy Policy.