Frequently Asked Questions

It's freemium. Every account gets 100 free validations after signing in with Google — no credit card required. Once those are used, you top up credits for $5 per 1,000 validations. There's no subscription and no daily fee; you only pay for what you check.

$5 per 1,000 validations, purchased in any quantity you choose (for example, 5,000 validations = $25). 1 credit = 1 successfully parsed number checked, whether it's a cache hit or not. Unparseable or invalid lines are never charged.

No. Credits you buy or receive as your free 100 never expire. Use them whenever you need them — next week or next year.

Each batch supports up to 100 numbers. You can run as many batches as you like, back to back — each one simply draws from your credit balance (100 free to start, then $5 per 1,000). Most users paste a CSV column or drop a CSV file and the validator streams results in under a minute.

Yes, a Google account. Sign-in is one click with Google — no separate password to create. You can still paste or upload your list and preview the parsed numbers before signing in; an account is only required to run the check, and it's what lets us track your credits and check history.

We used to run an ad-supported free tool with no account and no limits. We removed the ads and moved to a freemium credit model instead: 100 free validations per account, then $5 per 1,000. This funds the WhatsApp sessions and infrastructure directly instead of showing you ads, and results now download instantly with no wait.

No. Ads have been removed entirely. Downloads are instant with no countdown or banner.

The check is safe for you because it happens server-side using isolated pool sessions. Your own WhatsApp account is never involved and never contacted. WhatsApp does not notify the number owner that someone looked them up; the validation uses a registration lookup, not a message send.

Any CSV with one phone number per row works. Numbers can live in the first column or be detected automatically. We recommend E.164 format (for example +14155551234) because it removes ambiguity about country codes. Extra columns such as name or email are ignored, not stored.

Yes. The validator supports every country code WhatsApp serves. Numbers should include the plus sign and country code for best accuracy. The result screen shows a detected country label next to each number so you can spot misformatted entries at a glance.

BulkNumberChecker only validates whether a number is registered on WhatsApp. It does not send messages and is not a blast tool. Many marketing teams use the output CSV to clean their list before importing it into a compliant broadcast platform such as the WhatsApp Business API.

Accuracy tracks the WhatsApp registration endpoint, which is the same source most paid tools use. In practice, that means near-perfect results for recently-registered numbers. The one edge case is accounts deactivated in the last few hours; those occasionally appear active for a short window before propagation catches up.

Valid means the phone number is syntactically correct and routable by its carrier. Active means that number has a WhatsApp account attached to it. A number can be valid but inactive (no WhatsApp), or invalid entirely (wrong length, disconnected line). Our result screen uses the active status because that is what matters for WhatsApp outreach.

Numbers live in a short-lived result cache tied to your result URL and expire automatically after the TTL. We do not build profiles, we do not resell lists, and we do not retain the underlying phone numbers once the cache expires. Our privacy page has the full retention policy.

Yes. BulkNumberChecker offers a developer REST API secured by an API key, metered against the same credit balance as the web app — your 100 free credits apply here too. Create a key from your account, then POST numbers and receive a request_id you can poll for results. Full documentation and OpenAPI spec are at /developers.

Yes. Any AI agent or automation that can make authenticated HTTP requests can call the API with your key. Custom GPTs, Claude Skills, and MCP clients can wire it in as a tool using the OpenAPI spec at /developers.

Many paid tools require a monthly subscription, expire unused credits, or tie validation to your personal WhatsApp account (in the case of Chrome extensions). BulkNumberChecker is pay-as-you-go with no subscription, credits that never expire, and server-side checks that never touch your own WhatsApp account. For a side by side breakdown, see our comparison page.

Every country WhatsApp supports is supported here, including the United States, United Kingdom, Brazil, India, Indonesia, Nigeria, Mexico, Germany, Spain, and all of the European Union. The detection logic resolves the country by the leading digits of the E.164 number.