---
title: "Validate up to 100 addresses"
method: POST
path: "/email-validations/batch"
tags: ["Email validations"]
---

# Validate up to 100 addresses

`POST /email-validations/batch`

## Request

- Base URL: `https://api.poststack.dev`
- URL: `https://api.poststack.dev/email-validations/batch`
- Auth: one of:
  - HTTP bearer
  - OAuth 2
    - Authorization code: `https://poststack.dev/oauth/authorize`
    - Token URL: `https://poststack.dev/oauth/token`
- TypeScript: <https://skmtc.dev/poststack/apis/poststack-api/docs/email-validations/batch/post.ts> (a function with typed inputs; its response is checked against the schema)

## Request body

- ValidateEmailBatchInput
  - `emails` string[], required

## Response `200`

One result per address.

- object
  - `results` EmailValidation[], required
    - `email` string, required
    - `result` 'deliverable' | 'undeliverable' | 'risky' | 'unknown', required
    - `checks` object, required
      - `syntax` boolean, required
      - `mx` boolean, required
      - `disposable` boolean, required
      - `role` boolean, required
      - `free` boolean, required
    - `risk` 'low' | 'medium' | 'high', required

## Other responses

- `400`: Validation failed — `error` names each offending field (`field: message`).
- `401`: Missing, malformed or unknown credentials (`WWW-Authenticate: Bearer …` is set).
- `403`: The credential lacks the `email:send` scope (body `{ error: "insufficient_scope", required, missing }`), or the team is suspended.
- `429`: Rate limited (10/min). `Retry-After` gives the seconds to wait; `X-RateLimit-*` headers are sent on every response.

## Changes

- **2026-09-30** `4dc1e20989c8`: 12 warning
  - added the new `daily_limit_exceeded` enum value to the `anyOf[#/components/schemas/Error]/code` response property for the response status `403`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `400`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `401`
  - added the new `daily_limit_exceeded` enum value to the `code` response property for the response status `429`
  - …8 more
- **2026-09-29** `ef5b22b98333`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/poststack/apis/poststack-api/changes/email-validations/batch/post.md)

---

[API](https://skmtc.dev/poststack/apis/poststack-api.md) - [All operations](https://skmtc.dev/poststack/apis/poststack-api/llms.txt) - [OpenAPI document](https://skmtc.dev/poststack/apis/poststack-api/revisions/0d3971e3a670?raw)