> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sendkit.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Email Validation

> Verify email addresses before sending to reduce bounces, protect your reputation, and save money.

## Why validate emails?

Sending to invalid, disposable, or non-existent email addresses wastes resources and damages your sender reputation. Every bounce counts against you with email providers like Gmail and Outlook.

SendKit's email validation lets you **verify addresses before you send** — catching bad emails before they become bounces.

## What gets checked

Each validation runs multiple checks and returns a confidence level (`HIGH` or `LOW`) for each:

| Check            | What it detects                                                                          |
| ---------------- | ---------------------------------------------------------------------------------------- |
| **Syntax**       | Whether the email format is valid (e.g., missing `@`, invalid characters)                |
| **DNS**          | Whether the domain has valid MX records that can receive email                           |
| **Mailbox**      | Whether the specific mailbox exists on the mail server                                   |
| **Role address** | Whether it's a group address like `info@`, `admin@`, or `support@`                       |
| **Disposable**   | Whether it's from a disposable/temporary email service like Mailinator or Guerrilla Mail |
| **Random input** | Whether the local part of the email appears to be randomly generated characters          |

## Reading the results

Every validation returns a clear verdict:

* **`is_valid`** — Overall validity (`HIGH` = safe to send, `LOW` = risky)
* **`should_block`** — Boolean recommendation on whether to block the address
* **`block_reason`** — If blocked, the specific reason why:

| Block reason       | Meaning                               |
| ------------------ | ------------------------------------- |
| `invalid_syntax`   | The email format is malformed         |
| `invalid`          | The email is invalid or undeliverable |
| `disposable_email` | It's a throwaway address              |

## Using validation

### From the dashboard

Go to **Email Validation** in the sidebar, enter an email address, and get instant results. Your validation history is saved so you can review past checks.

### From the API

Validate an email programmatically via the [API](/api-reference/endpoint/validate-email). The response includes all evaluation fields so you can make your own decisions about what to block.

### Automatic validation on send

SendKit also validates recipients automatically when you send an email. If a recipient has invalid syntax or uses a disposable domain, the email is **blocked before it's sent** — protecting your reputation without any extra code.

<Note>
  Automatic validation on send uses local checks only (syntax, disposable). It doesn't consume credits. Credit-based validation via the API or dashboard includes deeper checks like DNS, mailbox verification, and more.
</Note>

## Credits

Each email validation costs **1 credit**. You can purchase credit packages from the dashboard under **Settings > Billing**.

* Credits are shared across your team
* Validations from both the dashboard and API consume credits
* If you run out of credits, the API returns a `402` error

### Auto-reload

You can configure auto-reload to automatically purchase more credits when your balance drops below a threshold. Set this up in **Settings > Billing** to avoid interruptions.

## Smart caching

SendKit caches validation results to save credits and speed up repeated lookups:

| Result        | Cache duration |
| ------------- | -------------- |
| Valid email   | 90 days        |
| Invalid email | 180 days       |
| Disposable    | Forever        |

If you validate the same email within the cache window, the cached result is returned instantly at no extra cost.

## FAQ

<AccordionGroup>
  <Accordion title="Does sending an email consume a validation credit?">
    No. Automatic validation during email sending uses local checks and is free. Only explicit validation requests (via API or dashboard) consume credits.
  </Accordion>

  <Accordion title="What's the difference between local and full validation?">
    Local validation checks syntax and disposable status using SendKit's own systems. Full validation (API/dashboard) additionally checks DNS records, verifies whether the mailbox actually exists on the mail server, and detects role addresses.
  </Accordion>

  <Accordion title="Should I validate every email before sending?">
    For transactional emails to known users (e.g., password resets), it's usually not necessary — SendKit's automatic checks handle bad addresses. For marketing campaigns or new signups, validating upfront helps reduce bounce rates significantly.
  </Accordion>

  <Accordion title="Can I validate emails in bulk?">
    Currently, the API validates one email per request. You can send multiple requests in parallel for bulk validation.
  </Accordion>
</AccordionGroup>