Verify single emails, run bulk jobs, find professional emails by name, embed the FoxGuard widget on any form, and manage your API keys and credits.
All REST endpoints require an API key via the X-API-Key header. Create keys in your dashboard.
fullAll endpointsverifyEmail verification onlyread-onlyGET requests onlyProtect any email input with one script tag. No API key required for the free public tier: 4 verifications per day per device.
Verify your first email in seconds.
curl -X GET "https://api.verifox.ai/v1/email-validation/john@example.com" \
-H "X-API-Key: vfx_your_api_key"{
"email": "john@example.com",
"domain": "example.com",
"isValid": true,
"reachable": "safe",
"syntax": true,
"smtp": {
"deliverable": true,
"catchAll": false,
"hostExists": true
},
"isFree": false,
"isRole": false,
"isDisposable": false,
"hasGravatar": true,
"suggestion": null,
"verifiedAt": "2026-03-31T10:30:00Z"
}5 modules · 22 endpoints
Verify individual emails or run bulk jobs. Checks syntax, SMTP deliverability, disposable providers, role accounts, and more.
GET/:emailPOST/POST/bulk+2 moreFind anyone's professional email address using their name and company domain. Uses smart permutation and SMTP verification.
POST/GET/:jobIdGET/history+2 moreDrop-in real-time email validation for any HTML form. Add two script tags before </head> — FoxGuard auto-discovers every [type="email"] input and validates as the user types. No backend changes. Supports a free public tier (4 req/day) and unlimited with an API key.
GET/validatePOST/public-verifyCreate and manage API keys for authenticating requests. Each key has a scope, optional IP restrictions, and an expiry. The full key is shown only once on creation — store it securely.
POST/GET/GET/analytics+1 moreCheck your Fox Credits balance, view the transaction history for every deduction and top-up, and pull usage statistics for dashboard charts.
GET/balanceGET/transactionsGET/statsHow it works
Every verification call runs the same 9-point engine that powers our email verification service: syntax against RFC 5321/5322, domain existence and MX records, a live SMTP handshake with a mailbox ping, disposable-domain matching, role-address detection, catch-all detection with AI-confidence scoring, domain age, and SPF/DKIM/DMARC authentication. That last mile matters: 20-40% of B2B lists fail at catch-all domains, and the confidence score is how you keep those addresses instead of discarding them as unknown. Accuracy measures 99.99% on our 1,000-address benchmark.
You integrate it three ways. The REST endpoints above handle real-time checks (median ~380ms per single verify, sub-50ms when cached) and asynchronous bulk jobs that process around 10,000 emails per minute on the standard tier. The Email Finder module turns a name plus a domain into a verified address, the API counterpart of the email finder tool. And if your stack is agentic, the email verification MCP server exposes the engine as native tool calls, no HTTP glue required.
Billing is Fox Credits: one credit per verification, pay-as-you-go, and credits never expire. Signup includes 1,000 free credits (2,500 with a work email), no card, and volume pricing is geo-localized on the pricing page. Want to eyeball results before writing code? The free email checker runs the same engine in the browser, 4 checks a day, no account. Forms that need protection without a backend can drop in the FoxGuard widget with a single script tag. Emails are processed in memory, never stored or sold, and the platform holds SOC 2 Type II with a 99.9% SLA on Starter and 99.99% on annual Volume contracts.
All errors return { error: string }
| Code | Status | Action |
|---|---|---|
200 | OK | Request completed |
201 | Created | Resource created |
202 | Accepted | Job started. Poll for results |
400 | Bad Request | Check your request parameters |
401 | Unauthorized | Invalid or missing API key |
402 | Payment Required | Insufficient Fox Credits |
404 | Not Found | Resource doesn't exist |
429 | Rate Limited | Slow down and retry after the window resets |
500 | Server Error | Retry after a short delay |
503 | Unavailable | Database unavailable. Retry shortly |
200OK
Request completed
201Created
Resource created
202Accepted
Job started. Poll for results
400Bad Request
Check your request parameters
401Unauthorized
Invalid or missing API key
402Payment Required
Insufficient Fox Credits
404Not Found
Resource doesn't exist
429Rate Limited
Slow down and retry after the window resets
500Server Error
Retry after a short delay
503Unavailable
Database unavailable. Retry shortly
Common questions
You pay in Fox Credits: one credit verifies one email, credits are pay-as-you-go, and they never expire. Signing up gives you 1,000 free credits (2,500 if you sign up with a work address), no card required. Volume rates are geo-localized, so check current credit pricing for your region rather than relying on screenshots or third-party comparisons.
Standard keys get 60 requests per minute on REST endpoints. When you exceed the window the API returns a 429; back off and retry after it resets. Bulk verification jobs run server-side at roughly 10,000 emails per minute on the standard tier, so large lists should go through the bulk endpoints instead of looping single-verify calls. Higher limits come with Volume contracts.
Use single-verify for real-time checks at the point of capture: median latency is around 380ms, and cached results return in under 50ms. For list cleaning, POST a bulk job instead; the API answers 202, processes asynchronously, and you poll for results. Looping the single endpoint over a list wastes your rate limit and finishes slower than one bulk job.
Verifox measures 99.99% accuracy on a 1,000-address benchmark list. Every call runs the same 9-point verification engine: syntax, domain and MX, live SMTP handshake, disposable and role detection, catch-all detection with AI-confidence scoring, domain age, and SPF/DKIM/DMARC checks. The catch-all scoring matters most for B2B lists, where 20-40% of addresses sit behind catch-all domains that simpler APIs mark unknown.
No. Addresses are processed in memory and never stored, logged, or sold. Verifox is SOC 2 Type II certified, which makes the API straightforward to clear with security review for GDPR-sensitive workloads. The only thing persisted is your usage count, so billing works without retaining the underlying addresses you verified.
Yes. Starter plans carry a 99.9% SLA, and annual Volume contracts step up to 99.99%. If you are wiring verification into a signup flow where downtime blocks registrations, design the call as a non-blocking check or queue retries; the plan comparison lists what each tier guarantees.
Two ways. The free email checker verifies 4 addresses a day in the browser with no account, useful for spot-checking results before you integrate. And the FoxGuard widget protects any form with one script tag; its free public tier needs no API key at all and covers 4 verifications per day per device.
Yes, natively. Beyond REST, Verifox ships an MCP server for email verification so agents built on Claude, Cursor, or any MCP-compatible runtime can verify addresses as a tool call without you writing HTTP glue. Same engine, same credits, same accuracy; the agent just gets a typed tool instead of a curl command.
Yes. The finder endpoints take a name plus a company domain, generate candidate patterns, and verify them against the live mailbox before returning a result, so you get deliverable addresses rather than guesses. Try it interactively with the email finder tool, then automate the same lookup through the Email Finder module documented above. Finder calls price in Fox Credits like verification.
Start free
Sign up, grab a key from the dashboard, and make your first call in under a minute. 1,000 free verification credits on signup, 2,500 with a work email. No card, and credits never expire.