Rate Limiting

Posta enforces rate limits to prevent abuse and ensure fair usage.

Email Rate Limits

Rate limits are applied per user:

Limit	Default	Environment Variable
Hourly	100 emails	POSTA_RATE_LIMIT_HOURLY
Daily	1,000 emails	POSTA_RATE_LIMIT_DAILY

When a rate limit is exceeded, the API returns 429 Too Many Requests:

{
  "success": false,
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Hourly email limit exceeded"
  }
}

Login Rate Limiting

Login attempts are rate-limited per IP address to prevent brute force attacks. This is enabled by default and can be toggled via the POSTA_AUTH_RATE_LIMIT_ENABLED environment variable.

Batch Emails

Each recipient in a batch send counts toward the rate limit. A batch of 100 recipients counts as 100 emails.

Configuring Limits

Adjust limits via environment variables:

POSTA_AUTH_RATE_LIMIT_ENABLED=true   # Set to false to disable login/register rate limiting
POSTA_RATE_LIMIT_HOURLY=500
POSTA_RATE_LIMIT_DAILY=5000

Administrators can also adjust rate limits dynamically via platform settings.