Best Email Testing · head-to-head

Testi@ vs Mailgun Inspect (formerly Email on Acid)

A sourced, side-by-side comparison for email testing. Testi@ has the lower entry price. Every figure links to the vendor's own page and the date we captured it.

Testi@ has the lower entry price — Testi@ starts at $0/mo, Mailgun Inspect (formerly Email on Acid) at $99/mo. Free tier: Testi@ Yes, Mailgun Inspect (formerly Email on Acid) No. HIPAA: Testi@ —, Mailgun Inspect (formerly Email on Acid) Yes.

As of 2026-06-18 · figures link to their source below

Side by side

Testi@

$0/mo entry
Entry price$0/mo (Free)
Free tierYes
HIPAA (BAA)
SOC 2
GDPR
Best forFreelancers

Mailgun Inspect (formerly Email on Acid)

$99/mo entry
Entry price$99/mo (Basic)
Free tierNo
HIPAA (BAA)Yes
SOC 2Yes
GDPRYes
Best forTeams already on Mailgun

Sources — Testi@: testi.at (verified 2026-06-18) · Mailgun Inspect (formerly Email on Acid): mailgun.com (verified 2026-06-18)

Key features

Testi@: Screenshots from ~50 email clients in seconds; Pay-as-you-go access periods (no subscription required); Spam testing included; Chrome extension for quick testing

Mailgun Inspect (formerly Email on Acid): 100+ email client and device previews; Accessibility testing and HTML code analysis; Link and image validation; Spam content checks on Premium+

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