Free Email Verifier Limits

A free email verifier is useful when you need a first look at an address or a tiny file. It becomes a problem when the unpaid tier is treated as a campaign cleaner. This article explains free email verification in practical terms: what kukudze’s Free plan gives you, what a syntax-and-format pass can catch, and how other vendors describe their own complimentary allowances. The goal is to pick a free email checker for the job it can actually do, then know when an email verifier free plan is no longer the honest tool.

For the product definition, read what an email verifier is. To compare format review with a mailbox check, see syntax check versus mailbox verification. Current figures live on the pricing page. You can create an account from sign-up. Try the email verifier once you have signed up and confirmed your email.

What unpaid tiers usually promise

Complimentary checkers tend to share a pattern, even when the numbers differ:

A monthly or one-time credit cap that is much smaller than a campaign file.
A narrower set of checks than the vendor’s paid cards.
A way to try the interface before you buy.

Those limits are not a trick. They exist so you can see the workflow. Trouble starts when a 500-row newsletter, or a form that collects addresses all month, is forced through an allowance that was meant for spot checks.

Read each vendor’s own page for what that unpaid offer includes. Do not assume another tool’s complimentary credits cover mailbox-level flags, and do not assume a “free” downloadable script is doing the same work as a live verifier. For paid and unpaid plans side by side, see the buyer’s guide to email verifiers.

What kukudze’s Free plan includes

kukudze shows a $0 Free plan on its pricing page. It gives you 100 checks a month and takes lists up to 50 rows. You sign up for a free account and confirm your email before the first check. Checks reset each month.

Free runs the same 4 checks as every paid plan: the format of the address, whether the domain can receive mail, the mailbox answer (the mail server is asked if it accepts the address; no email is sent), and whether the domain accepts all mail. Each row comes back Valid, Invalid, Risky or Unknown, and you can download the results as a CSV. Your lists and results are not stored on kukudze’s servers.

100 checks a month is enough to check new signups by hand, clean a short contact list before a personal send, or test a sample from a bigger file before you decide what to do with it. It is not enough to clean a typical newsletter or outbound campaign file in one go.

What a syntax and format pass can catch

A format review asks whether the string even resembles a mailbox name plus domain. It can surface:

A missing @ or a missing domain.
Spaces or illegal characters that a mailbox name should not contain.
Many incomplete pastes from a spreadsheet.

That work is real. It is also the same class of problem a careful person, or an HTML type=”email” field, can often see. The syntax versus mailbox article walks through why passing this layer does not mean anyone collects mail at that string.

A neatly written address on a domain that no longer accepts mail will sail through syntax. So will a disposable inbox with a legal local part. So will many role addresses. If your next action is a campaign send, you need the domain and mailbox checks too, not only a cleaner-looking spreadsheet. kukudze runs those on every plan, Free included.

What a free plan cannot do

kukudze’s Free plan runs the full set of checks, so its limits are about volume and about things kukudze does not check on any plan:

Lists longer than 50 rows in one go.
More than 100 checks in a month.
Flags for temporary inboxes, role addresses such as info@, or spam traps. kukudze does not detect these on any plan.
Checks from your own app. kukudze has no public API; you check addresses on the site, one at a time or as a list.

The paid plans only add more checks and bigger lists. Starter is $9 a month for 2,000 checks and lists up to 1,000 rows. Pro is $19 a month for 5,000 checks and lists up to 5,000 rows. Agency is $39 a month for 15,000 checks and lists up to 15,000 rows. All three are coming soon and cannot be bought yet, so Free is the only plan open today. The checks are the same on every plan.

So the question is not which plan checks more deeply. It is how many addresses you need to check each month. For temporary inboxes and role addresses, filter the sheet yourself. For spam traps, rely on clean collection and double opt-in.

How other vendors describe their complimentary allowances

Other tools publish their own free email verification offers. The notes below come from each vendor’s page. Revisit those pages before you depend on the numbers, because complimentary caps change.

ZeroBounce. ZeroBounce’s complimentary verifier page grants 100 checks each month after registration that uses a business domain or a premium domain. ZeroBounce states that signup condition on that page.

Hunter. On Hunter’s Email Verifier page, visitors may complete five lookups each day before they create a login. Hunter pricing shows a $0 Free plan that grants 50 credits every month. According to Hunter’s credit article, checking one address costs 0.5 credits. Because those credits also power other Hunter features, search or finder activity shrinks the remainder available for verification.

NeverBounce. NeverBounce documents, in its pricing and billing help article, a gift of 10 credits at signup, with each credit covering a single check. The NeverBounce pricing page adds that you can begin without entering a card and can check an initial list that way.

Kickbox. Kickbox’s getting-started document states that registration costs nothing, that opening the account does not ask for a card, and that 100 complimentary checks come with that account.

Bouncer. Bouncer’s pricing page includes the line “100 free credits for a start.” A separate note on that page says on-demand purchases do not expire.

Notice how different these offers are. Some refresh each month. Some are a one-time handful of credits at registration. Some require a business domain to unlock the complimentary bundle. A “free email verifier” comparison that ignores those details will pick the wrong tool for the wrong job.

kukudze’s Free plan sits in the middle on numbers: 100 checks a month, with lists up to 50 rows. What sets it apart is that Free runs the same 4 checks as the paid plans, so a free result is not a cut-down result. Compare the job, not only the headline number.

Checks, retries, and when 100 a month runs out

A monthly figure is a budget for checks, not a promise that 100 unique campaign rows will be checked. If you upload the same practice file twice, you may spend twice. Remove duplicates before you upload, and keep your downloaded results so you do not check the same rows again. Checks reset each month.

Lists are capped at 50 rows on Free. A file of 300 rows has to be split into parts, and 100 checks covers only two full lists a month. Results are shown in your browser and you download them. kukudze does not keep your lists on its servers, so save each CSV before you move on.

The jobs that fit 100 checks a month are small. A founder can check the week’s new signups. A support person can check a few addresses that bounced or look mistyped. A marketer can test a sample from an inherited spreadsheet before deciding what to do with the rest. Once the job is a full campaign file of thousands of rows, Free is too small, and the bigger plans are not on sale yet.

When the free plan is not enough

Free stops being the right tool when one or more of the following applies:

You need to check more than 100 addresses a month, or one list is longer than 50 rows.
You need to check signups inside your own app as they arrive. kukudze has no public API, so that needs another tool.
You want flags for temporary inboxes, traps, or role mailboxes. kukudze does not detect these on any plan, so filter them yourself or use a tool whose page lists them.

The paid plans add only more checks and bigger lists, and they are coming soon, not on sale yet. Until then, split a larger file across months, or check the rows that matter most first, such as new or long-idle contacts.

FAQ

Is there a completely free way to verify that a mailbox exists?

Yes. kukudze’s Free plan asks the mail server whether it accepts the address, the same mailbox check every paid plan runs, for up to 100 addresses a month. No email is sent. Some other vendors also run full checks on their free allowance; read the page you will use. A browser format field is not a mailbox check.

Can I split a large file across several months of free checks?

You can. Free gives 100 checks each month and takes lists up to 50 rows. But the list keeps aging while you wait, so check the rows you will mail first. For a big file you need now, Free is too small, and the paid plans are not on sale yet.

Does signing up automatically start a paid subscription?

No. kukudze’s Free plan is $0, and the paid plans cannot be bought yet. Create an account from sign-up and confirm your email to start. Other vendors describe their own trials on the pages linked above; this article does not speak for their billing systems.

Why do complimentary caps differ so much from vendor to vendor?

They are marketing and product choices, not a shared industry standard. ZeroBounce ties a monthly bundle of 100 to registration with a business domain or a premium domain. NeverBounce grants 10 credits at registration. Kickbox grants 100 verifications without a credit card. Hunter shares a 50-credit monthly wallet across more than verification. kukudze gives 100 checks a month that run the same 4 checks as its paid plans. Compare what you receive, not only how many tokens are advertised.

Should I use a free competitor just to get mailbox-level results?

Not for small lists. kukudze’s Free plan already returns mailbox-level results. For a bigger file, another vendor may fit if its own page says its free credits run the same checks as its paid product. Then read its cap and any domain or signup rules.

Wrapping up

A free email verifier is a starting point. On kukudze, the starting point is 100 checks a month, lists up to 50 rows, and the same 4 checks as every paid plan. That will catch broken strings, domains that cannot receive mail, and mailboxes the server refuses. Other vendors publish different complimentary numbers and different rules for unlocking them; take those numbers from their pages. When the next action is a big campaign, make sure your plan has enough checks for the whole file, and filter temporary and role addresses yourself.