APIVerified~130ms avg
Postmark API
Transactional email with industry-leading deliverability.
Install
npm install postmark
About
Postmark focuses exclusively on transactional email and does it well. Send emails with templates, track delivery, manage servers and message streams, and handle inbound email processing. 95K weekly downloads. Known for the best deliverability in the industry with guaranteed delivery times. Choose Postmark when email reliability is critical.
Tags
postmarkemailtransactionaldeliverability
Score Breakdown
CLI Score Breakdown8/11
✓Official SDK on npm/pip+2
✓Env var authentication (no browser OAuth)+2
✓Works in headless/CI environments+2
✗CLI tool available0
✓JSON response for piping/parsing+1
✓Docs have curl/CLI examples+1
✗Reasonable rate limits for scripted use0
✗Machine-readable pricing (md/JSON/static)0
Quality Score Breakdown
npm weekly downloads95k
GitHub stars250
Days since last release18d
Issue close ratio78%
TypeScript typesYes
Docs qualitygood
Breaking changesrare
Performance
Latencyus-east-1 - 2026-03-26
p50
105ms
avg
130ms
p95
330ms
Scores
CLI
8
Quality
7
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