# MailSift, free, Free, POST /verify/bulk, Verify a CSV in bulk: Email validation API

> MailSift is a fast, accurate email verification API and bulk CSV validator. It detects invalid, disposable, role-based, and risky email addresses using syntax, MX, SPF, DMARC, SMTP, and catch-all checks, returning a status and a 0–100 deliverability score.

MailSift's email validation API on its Free plan, $0.00 per 1,000 emails. 3 of the 6 key fields: Address, Its check, Confidence.

- This page: https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-bulk-verify-a-csv-in-bulk
- Get it: https://mailsift.dev/pricing
- Its API docs: https://mailsift.dev/api#bulk-workflow
- Sold by: MailSift (https://mailsift.dev)
- Checked: 2026-10-20

## In the answer

- Completeness: 50%
- Address: ✓
- Its check: ✓
- Confidence: ✓

## Price

- $ per 1,000: $0.00
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Per: result
- Also pays for: from the same budget: Verify one email · Verify one email with Deep Verification · Verify up to 100 emails at once · Verify up to 100 emails at once with Deep Verification · Verify a CSV in bulk with Deep Verification

## Not found

- $ per 1,000: $0.00

## Catch-all

- $ per 1,000: $0.00

## In their words

- Their pitch: MailSift is a fast, accurate email verification API and bulk CSV validator. It detects invalid, disposable, role-based, and risky email addresses using syntax, MX, SPF, DMARC, SMTP, and catch-all checks, returning a status and a 0–100 deliverability score.

## Data

- Freshness: live
- Keep data: no limit
- Use data: You may not use MailSift to: send unsolicited email, harass individuals, build databases of contact information for sale, circumvent rate limits or terms, or for any unlawful purpose. [...] You are responsible for having a lawful basis to process the email addresses you submit, including, where applicable, consent under the GDPR. [...] We grant you a non-transferable, revocable license to use the service for its intended purpose.

## Plan

- Pay: $0
- You get: 500 credits
- Enough for: 500 results, once
- Expires: never

## Rate limit

- Per second: 1

## Speed

- Answer: by polling or webhook

## The call

- You send: file. Optional: mode
- Method: POST
- Path: /verify/bulk

## About the plan

- Plan: Free
- Who can get it: anyone 16 or older

## The 31 fields the plan's answer can hold

job ID, filename, total rows, processed rows, valid count, invalid count, risky count, unknown count, job status, mode, credits reserved, error message, started at, completed at, created at, email, status, sub-status, score, disposable, MX, role address, free provider, relay, blocklisted, SPF, DMARC, domain age, MX provider, normalized email, typo suggestion

## MailSift's plans (5)

- [MailSift, free, Free, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-bulk-verify-a-csv-in-bulk/llms.txt): $0.00 per 1,000, 50% complete, live
- [MailSift, $10 pack, Starter, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/10-pack-starter-post-verify-bulk-verify-a-csv-in-bulk/llms.txt): $0.40 per 1,000, 50% complete, live
- [MailSift, $35 pack, Growth, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/35-pack-growth-post-verify-bulk-verify-a-csv-in-bulk/llms.txt): $0.35 per 1,000, 50% complete, live
- [MailSift, $99 pack, Pro, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/99-pack-pro-post-verify-bulk-verify-a-csv-in-bulk/llms.txt): $0.283 per 1,000, 50% complete, live
- [MailSift, $249 pack, Enterprise, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/249-pack-enterprise-post-verify-bulk-verify-a-csv-in-bulk/llms.txt): $0.249 per 1,000, 50% complete, live

## MailSift's calls (6)

- `POST /verify/bulk`, Verify a CSV in bulk: [MailSift, free, Free, POST /verify/bulk, Verify a CSV in bulk](https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-bulk-verify-a-csv-in-bulk/llms.txt)
- `POST /verify/bulk`, Verify a CSV in bulk with Deep Verification: [MailSift, free, Free, POST /verify/bulk, Verify a CSV in bulk with Deep Verification](https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-bulk-verify-a-csv-in-bulk-with-deep-verification/llms.txt)
- `GET /verify`, Verify one email: [MailSift, free, Free, GET /verify, Verify one email](https://datacircle.dev/validate-email-apis/mailsift/free-free-get-verify-verify-one-email/llms.txt)
- `GET /verify`, Verify one email with Deep Verification: [MailSift, free, Free, GET /verify, Verify one email with Deep Verification](https://datacircle.dev/validate-email-apis/mailsift/free-free-get-verify-verify-one-email-with-deep-verification/llms.txt)
- `POST /verify/batch`, Verify up to 100 emails at once: [MailSift, free, Free, POST /verify/batch, Verify up to 100 emails at once](https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-batch-verify-up-to-100-emails-at-once/llms.txt)
- `POST /verify/batch`, Verify up to 100 emails at once with Deep Verification: [MailSift, free, Free, POST /verify/batch, Verify up to 100 emails at once with Deep Verification](https://datacircle.dev/validate-email-apis/mailsift/free-free-post-verify-batch-verify-up-to-100-emails-at-once-with-deep-verification/llms.txt)

## Similar plans of other providers

- [Melissa, free, Monthly Top-off, GET /V4/WEB/GlobalEmail/doGlobalEmail](https://datacircle.dev/validate-email-apis/melissa/free-monthly-top-off-get-v4-web-globalemail-doglobalemail/llms.txt): $0.00 per 1,000, 50% complete, live
- [Minelead, free](https://datacircle.dev/validate-email-apis/minelead/free/llms.txt): $0.00 per 1,000, 50% complete, live
- [MailValidation.io, free, Free, POST /api/validate/](https://datacircle.dev/validate-email-apis/mailvalidation-io/free-free-post-api-validate/llms.txt): $0.00 per 1,000, 33% complete, live
- [MyEmailVerifier, free, 100 free credits daily, GET /verifier/validate_single/{email}/{API_KEY}](https://datacircle.dev/validate-email-apis/myemailverifier/free-100-free-credits-daily-get-verifier-validate-single-email-api-key/llms.txt): $0.00 per 1,000, 33% complete, live

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-10-20.

- https://mailsift.dev
- https://mailsift.dev/api
- https://mailsift.dev/docs/api-reference.md
- https://mailsift.dev/docs/overview.md
- https://mailsift.dev/llms.txt
- https://mailsift.dev/openapi.json
- https://mailsift.dev/pricing
- https://mailsift.dev/terms