About BulkNumberChecker

Why we built it

The existing paid tools price out the people who need validation the most. A freelance marketer with a client list of twenty thousand numbers should not have to spend two hundred dollars on credits every time the list refreshes. A researcher studying messaging adoption in emerging markets should not need to negotiate an enterprise contract to run a one-off batch. We watched friends pay monthly subscriptions to tools they used for ten minutes a week, and we knew the same validation could be delivered far cheaper if the pricing matched actual usage instead of a recurring plan. So we built a pay-as-you-go alternative instead.

We used to run this tool ad-supported and free for everyone. We removed the ads and moved to a straightforward credit model: 100 free validations per account, then $5 per 1,000. It funds the WhatsApp sessions and infrastructure directly, and it means every download is instant — no ad wall, no countdown timer.

How it works, in plain English

When you paste a list of numbers or drop a CSV file, the batch is queued on our servers. A pool of isolated sessions checks each number against the WhatsApp registration directory, which is the same directory the official app uses when you type a new contact into a chat. Every number comes back with one of two answers: active on WhatsApp or not active. The result page shows the numbers in a clean table, flags country codes, and lets you download a CSV of just the active entries.

Nothing here uses your personal WhatsApp account. No Chrome extension injects code into your session. No browser tab needs to stay open. The work happens on our infrastructure so your number never gets associated with the check.

Privacy is the default

Signing in with Google gives us your email and name so we can track your credits and check history — nothing more, and we never see your Google password. Buying credits is handled entirely by Lemon Squeezy, our payment processor; we never see or store your card details. The numbers you submit live in a short-lived result cache, scoped to the single result URL we generate for you, and that cache expires automatically after its TTL. We do not aggregate your list, we do not resell leads, and we do not train models on your data. If you want to dig deeper, the privacy page spells out the exact retention windows and third-party relationships.

The team

BulkNumberChecker is built by a small group of engineers and marketers who have spent years running outreach programs and maintaining contact databases. We know what a sixty-thousand-row list looks like at 2 AM, and we know what it costs when half of it is dead. The tool is the one we wished existed when we were on the other side of the invoice.