VaultSandbox Self-Hosted SMTP Testing Gateway

Explore this developer service’s ongoing no-cost allowance, restrictions and official documentation before deploying.

INCLUDED FREE ALLOWANCEApache-2.0 licensed self-hosted SMTP testing gateway with web UI, REST API, SPF/DKIM/DMARC checks, TLS and configurable email retention; no software quota or expiration stated.

View official documentation

Plan details

What do these plan and deployment labels mean?

Plan: Ongoing free allowance
Deployment model: Self-hosted
Credit card: Not required
Commercial use: Allowed
Added to directory (UTC): 2026-11-05
Last checked: 2026-11-05

Important restrictions

Public Beta; self-hosted receive-only testing gateway, not a free hosted email-sending service. Provide compute, storage, DNS or VSX DNS, and reachable ports; 7-day retention is the configurable default. Infrastructure costs apply.

View official documentation

Independent community listing, not affiliated with the provider. Always check the latest billing policy and quotas before enabling paid usage.