Postmarkapp
Developer-focused transactional and marketing email delivery via API and SMTP
Overview
Postmarkapp (postmarkapp.com): Developer-focused transactional and marketing email delivery via API and SMTP. Category on TopCheckouts: Developer tools.
In September 2026, Similarweb estimates about 10,969 visits went from Postmarkapp to a checkout payment page — #318 of the 607 sites we track. That is 125% up from the April–June monthly average of 4,872.
Total website visits that month were about 211,195 (Similarweb 3-month total, split by Semrush monthly trend). Roughly 5.2 of every 100 visits reached the checkout page.
Largest September traffic sources: direct 84%, search 16%, AI assistants 0%. (Source breakdown from Semrush, desktop only.)
New-user source is unclear: mostly direct visits (about 84%) with no visible invite or sharing mechanics, so new users likely come from word of mouth, private channels or off-site communities.
Pricing: $15/mo (10,000 emails).
Checkout visits over time
By checkout
| Checkout | Apr–Jun avg | Jul | Aug | Sep |
|---|---|---|---|---|
| invoice.stripe.com | 4,872 | 8,874 | 13,314 | 10,969 |
Similarweb referral data; months derived from 1/2/3/6-month shares.
Website traffic & engagement
Traffic sources
Semrush source breakdown (desktop)
How the new-user source is computed
Direct + brand search 96.1% · Direct and brand search count as viral only when the site shows sharing mechanics; the largest share wins, under 5% means Other.
Search & AI
Social & referrals
Visitor countries
Product & pricing
“Try Postmark free ... No Credit Card Required / $15 per month for 10,000 emails / one of my heroes in the bootstrapped world”Quote from the site
FAQ
How many checkout visits does Postmarkapp get per month?
In September 2026, Similarweb estimates about 10,969 visits went from Postmarkapp to a checkout payment page — #318 of the 607 sites we track. That is 125% up from the April–June monthly average of 4,872.
Where do Postmarkapp's new users come from?
New-user source is unclear: mostly direct visits (about 84%) with no visible invite or sharing mechanics, so new users likely come from word of mouth, private channels or off-site communities.
How much does Postmarkapp cost?
Pricing: $15/mo (10,000 emails).
Similar sites
About the data
Checkout visits are Similarweb's estimate of visits from this site to a checkout payment page; opening checkout is not paying, so this is not revenue. See the methodology for how website visits and source mix are computed. Updated 2026-10-21.