Keeping Your Email API Key Secure
Practical rules for storing, scoping and rotating email API keys so a leak never becomes a spam incident.
An email API key can send mail as your brand. Leak one and an attacker can spam from your domain and torch your reputation. Treat it like a password.
Storage
- Keep keys in environment variables or a secrets manager.
- Never commit them to git or ship them to the browser.
- Use server-side calls only — the key never touches client code.
Scope and rotate
Use separate keys per environment and service so you can revoke one without breaking everything. Rotate on a schedule and immediately if you suspect exposure.
Send email that actually lands in the inbox
API and visual editor, SPF/DKIM/DMARC out of the box, analytics and warm IPs. Free tier — 200 emails/month, no card required.
If a key leaks
Revoke it instantly, issue a new one, and check your delivery log for unexpected sends. Fast revocation is your best damage control.
Built for it
Sendersy supports multiple revocable API keys and a delivery log you can audit. Start free.
Explains how to send email from code. Loves clean SDKs, idempotency and sane webhooks.
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