Limits

The published numbers that bound every client — the API, the MCP server, the 1mail CLI, and the web viewer all read the same inboxes under the same limits.

Every inbox at 1mail.dev is public. Anyone who knows the address can read it. Never use these addresses for anything sensitive — or any account you care about.

Published limits

Every API response carries advisory RateLimit-Limit / -Remaining / -Reset headers; a 429 adds Retry-After — see errors on the API page.

Limit	Value
Reads, per inbox	60 / 60 s
Reads, per IP	600 / 60 s
Inbound, per sender	300 msgs / 60 s
Max message size	5 MiB
Retention	24 hours
Inbox cap	2,000 messages