Best email verification API for developers: SDKs and price at 50,000 calls a month

Which one should you pick?

• Pick SimpleVerifier if you verify or re-check lists every month and want one flat monthly price instead of credits, with catch-all addresses kept risky rather than marked valid.

  Skip SimpleVerifier if you want the lowest price for one small list, where another vendor's pack can cost less (cost by list size); you need your data processed only inside the EU (our service providers process data in several countries, including the US); or your list is mostly Outlook.com, Hotmail or Live addresses, which Microsoft currently won't let us confirm, so they come back risky (why).

• Pick Verifalia if you clean a few thousand addresses once, or need multi-pass re-tries on slow mail servers, and want credits that never expire.

• Pick ZeroBounce if you want inbox placement tests, blacklist monitoring and warmup in the same account as verification.

• Pick Listclean if you clean a list of up to about 100,000 once or a few times a year and want credits that never expire.

• Pick Proofy if you clean a list of up to about 25,000 once or a few times a year and want credits that never expire.

• Pick Bulk Email Checker if you clean a list of up to about 25,000 once or a few times a year and want credits that never expire.

• Pick Reoon if you clean one list once, or a few hundred addresses a day, and want the lowest per-address price with credits that never expire.

• Pick Verimail if you verify up to about 10,000 addresses a month, or clean a list now and then and want credits that never expire.

• Pick DeBounce if you clean small or one-off lists and want credits that never expire, with no subscription to cancel.

• Pick Bouncify if you verify about 10,000 to 30,000 addresses a month at a steady rate, or clean a list once and want packs that never expire.

How we compared

We priced 50,000 a month on the verifiers whose dated notes in our data name an API or SDK, from our dated vendor data, and list each vendor's pricing page under its row. The table shows SimpleVerifier and the 9 lowest-priced of the API-listing vendors priced at this size; vendors with no published price at this size are left out. API metering differs by vendor (some share one credit pool with file uploads), so check the vendor's own page before you build on a number. We did not run an accuracy benchmark, so nothing here ranks accuracy: test a shortlist on a sample of your own list, including addresses you know are dead.

Each tool in a few lines

1. 1. SimpleVerifier(our tool)

   Best for: Node.js and Python SDKs, API docs and an MCP server, on a flat monthly plan

   • Catch-all addresses come back risky, never guessed valid
   • Connects to Instantly, Smartlead, HubSpot and Mailchimp by API key
   • Watch out: The free allowance is a one-time 100 checks, not a monthly refill
   • Watch out: Starter has no API and its allowance does not roll over; 10,000 a month needs Pro

   Checked November 10, 2026: SimpleVerifier pricing · SimpleVerifier verify

2. 2. Verifalia

   Best for: Buyers who need repeated passes on slow or greylisting mail servers. Its High (3 passes) and Extreme (9 passes) quality levels re-try addresses with temporary problems, and its SDKs cover .NET, Go, Java, JavaScript, PHP and Ruby

   • Small one-off jobs are cheap: 1,000 credits are $7.90 and 5,000 are $28.90, and credits from packs never expire.
   • Its High (3 passes, 50 seconds of greylisting wait) and Extreme (9 passes, 2 minutes) quality levels re-try addresses with temporary problems, at 2 and 4 credits each.
   • Watch out: The plans are daily allowances that expire at midnight, so a large list either waits for days of credits or is bought as a pack, and High or Extreme quality doubles or quadruples the credits per address.

   Checked November 2, 2026: Verifalia plans and pricing

3. 3. ZeroBounce

   Best for: Teams that want a deliverability suite in one plan

   • ZeroBounce ONE ($99 a month) bundles 10,000 validations with 10,000 email finds, 100 inbox placement tests, blacklist monitoring and 250 warmup seeds.
   • Credits never expire while a ZeroBounce ONE subscription is active, and unknown results are not charged.
   • Watch out: Credits are the unit, so the bill scales with list size and a re-verification of the same list costs full price again.

   Checked October 30, 2026: ZeroBounce pricing · ZeroBounce integrations

4. 4. Listclean

   Best for: Buyers who clean a list once or now and then: its packs are $15 for 25,000 and $35 for 100,000, credits never expire, and unknown and duplicate results are not charged

   • One-off cleans cost less: 25,000 credits are $15 and 100,000 are $35, under a month of Pro.
   • Its FAQ says credits never expire, and unknown and duplicate results are not charged.
   • Watch out: Every pass is another pack, so a list you re-check every month is paid for again each time, and from 250,000 addresses ($65) one pass costs more than a month of Pro.

   Checked November 4, 2026: Listclean pricing and FAQ

5. 5. Proofy

   Best for: Buyers who clean a list of up to about 25,000 once or now and then: its packs are $18 for 10,000 and $32 for 25,000, credits never expire, and unknowns and duplicates are not charged

   • Small and mid-size one-off cleans cost less: 10,000 credits are $18 and 25,000 are $32, and its page says credits never expire, on packs and monthly plans alike.
   • Its pricing page says duplicates and Unknown results are not charged.
   • Watch out: Every pass is another credit purchase, so a list you re-check every month is paid for again each time, and from 50,000 a month its monthly plan ($44.20) costs more than a month of Pro.

   Checked November 3, 2026: Proofy pricing and FAQ · Proofy free email checker

6. 6. Bulk Email Checker

   Best for: Buyers who clean a list once or a few times a year: 10,000 credits are $9.95 and 25,000 are $23.95, credits never expire, and there is no monthly fee

   • One-off cleans cost less: 10,000 credits are $9.95 and 25,000 are $23.95, with no monthly fee.
   • Its pricing page says credits never expire and stay valid for as long as the account is active.
   • Watch out: Every pass is another credit purchase, so a list re-checked every month is paid for again each time, and from 50,000 credits ($44.95) one pass costs more than a month of Pro.

   Checked November 4, 2026: Bulk Email Checker pricing and FAQ

7. 7. Reoon

   Best for: Buyers who want a one-off clean at a low per-address price. Its smallest instant pack is 10,000 credits for $11.90, which undercuts a month of SimpleVerifier for a single pass

   • A single pass is cheap: its smallest instant pack is 10,000 credits for $11.90, and instant credits never expire.
   • Unknown results are never charged; its FAQ says they are refunded automatically when the task finishes.
   • Watch out: The subscription is a daily allowance that does not carry over, so a large list either waits for days of credits or is bought again as an instant pack.

   Checked November 3, 2026: Reoon email verifier pricing and FAQ

8. 8. Verimail

   Best for: Up to about 10,000 a month

   • Its Starter plan is $15 a month for 10,000 credits, and packs start at $4 for 1,000.
   • Its pricing page says unknowns, duplicates and syntax errors are never charged, and pack credits never expire.
   • Watch out: It has no plan between 10,000 and 100,000 a month, so 25,000 a month is a $40 pack or the $79 Professional plan, and 1,000,000 a month is $299.

   Checked November 5, 2026: Verimail pricing and FAQ

9. 9. DeBounce

   Best for: Small and one-off lists on credits that never expire

   • Pay-as-you-go credits never expire, and every feature is included on every plan, API included.
   • Duplicates are removed for free, so you never pay twice for the same address in one list.
   • Watch out: Every option is metered by the credit, so every pass over the list is billed again — the cost scales with how often you clean, not just how much.

   Checked November 2, 2026: DeBounce pricing

10. 10. Bouncify

    Best for: your volume is steady and modest. $19 a month for 10,000 verifications undercuts us at that volume, and its pay-as-you-go packs never expire

    • Its $19 monthly plan covers 10,000 verifications, less than a month of Pro for that volume.
    • Pay-as-you-go packs never expire, from $12 for 3,000 to $599 for 1,000,000.
    • Watch out: Subscription credits reset every month, so an allowance you did not use that month is gone.

    Checked November 3, 2026: Bouncify pricing

Common questions

Which SDKs does SimpleVerifier ship?

Official Node.js and Python clients, plus an open-source disposable-domain list; the SDK docs show install and examples. There is also an MCP server for AI agents.

How do I start with the API?

Create a key and follow the quickstart; the API reference lists endpoints and error codes. An API key comes with Pro and above.

Which route is cheapest for me?

It depends on volume and how often you repeat it. At 50,000 a month the lowest published routes are Verifalia ($219) and ZeroBounce ($379); see cost by list size to price another volume. SimpleVerifier Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off.

Is the cheapest verifier the most accurate?

We did not run an accuracy benchmark, so nothing here ranks accuracy: test a shortlist on a sample of your own list, including addresses you know are dead.