Comparison

Email on Acid vs Maildev

No leader: the top candidate Maildev has only 0.24 confidence (low), below the 0.35 needed to declare a winner. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.

Machine formatsJSONMarkdownGraphQLor send Accept: application/json
Email on Acid58
Maildev64
Score
Vioscale score
Email on Acid58 / 100medium · 66%updating
Maildev64 / 100low · 24%updating
Pricing
Free tier
Email on Acid
Maildev
Model
Email on Acidcommercial
Maildevcommercial
Price level
Email on Acidhigh
Maildevfree
Starting price
Email on Acid$99
Maildev
Transparent
Email on Acid
Maildev
Security
Gdpr
Email on Acid
Maildev
Iso27001
Email on Acid
Maildev
Scorecard
Email on Acid
Maildev4.6
Soc2
Email on Acid
Maildev
Reliability
Sla pct
Email on Acid99.9
Maildev
Adoption
Dependent repos
Email on Acid
Maildev313
Github stars
Email on Acid
Maildev6,032
Activity
Commits last 30d
Email on Acid
Maildev24
Release
Cadence days
Email on Acid
Maildev46
History
Email on Acid
Maildev20 items
License
Spdx
Email on Acid
MaildevMIT
Language
Primary
Email on Acid
MaildevTypeScript
Market
Availability

Capabilities

Feature-by-feature on the axes that matter for email testing dev. “-” means undocumented, not absent.

Capabilities
API assertions
Email on Acid
Maildev-
Rendering preview
Email on Acid
Maildev-
Spam score check
Email on Acid
Maildev-
Blocklist deliverability check
Email on Acid
Maildev-
SMS testing
Email on Acid
Maildev-
Production sending addon
Email on Acid
Maildev-
Ci cd integration
Email on Acid
Maildev-
Multi user inboxes
Email on Acid
Maildev-
Open source
Email on Acid
Maildev-

What each one is

The product in its own terms, so the numbers below have context.

Email on Acid

Tests email campaigns across 100+ email clients and devices to identify rendering issues, validate content for inbox compatibility, check accessibility compliance, and detect deliverability problems before sending.

Independently observed

Maildev

Runs as a local SMTP server with a web inbox interface to capture and review emails generated by your application during development. Supports AI agent integration through the Model Context Protocol for automated email inspection.

Independently observed

Pricing

List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.

Email on Acid

from $99/moSubscription7-day trial

From $99/month. 7-day free trial.

  • Basic$99/month, $0.15 per preview overage
    • 1,000 email previews per month
    • 100+ email preview clients and devices
    • Unlimited users
    • API access
    • Overage charges for additional previews
  • Premium$199/month
    • 2,000 email previews per month
    • 100+ email preview clients and devices
    • Unlimited users
    • Accessibility tests (WCAG 2.2 / European Accessibility Act compliance)
    • HTML code analysis
    • +2 more
  • CustomContact sales
    • Custom preview allotments
    • Phone and chat support
    • Dedicated support documentation
as of verify ↗

Maildev

FreeFree tier

Free & open source (MIT)

as of verify ↗

Platform & deployment

Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.

Platforms
Web
Email on Acid
Maildev
CLI
Email on Acid
Maildev
Deployment
Cloud / SaaS
Email on Acid
Maildev
Self-hosted
Email on Acid
Maildev

Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.