Limits
Sizes, lifetimes, and quotas.
| Limit | Value |
|---|
| Temporary inbox lifetime | 1 hour |
| Temporary inboxes per organization | No limit |
| Permanent addresses per organization | 5 |
| Permanent address name | 3–48 characters on the shared domain, 1–48 on your own domains: a–z, 0–9, ., _, -; starts and ends with a letter or digit |
| Messages in a permanent inbox are kept | Until the address is deleted |
Reserved names that cannot be registered on the shared domain: abuse, admin, hostmaster, mailer-daemon, postmaster, root, security, support. On your own domains these names are allowed.
| Limit | Value |
|---|
| Message size | 5 MiB, larger mail is rejected with 552 |
| Recipients per delivery | 50 |
| Parsed text and HTML | 1.5 MB combined. Above that, html is empty and text is cut off. |
| Unknown or expired address | Rejected with 550 |
| Limit | Value |
|---|
| Wait timeout | Default 15 s, maximum 120 s |
| Concurrent waits | 4 per API key |
| API key name | 2–80 characters |
| API key expiry | Never, or 1–365 days |
| Limit | Value |
|---|
| Sends per organization | 60 per minute, then 429 |
| Message size | 5 MiB, larger messages return 400 |
| Recipients per send | 1; over SMTP 50, each counting as one send |
| Limit | Value |
|---|
| Domains per organization | 3, pending domains included |
| Limit | Value |
|---|
| Password | At least 10 characters |
| Organizations per user | 10 |
| Members per organization | 100 |
| Invitation link validity | 7 days |
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