MailCatcher

● Identity checked

Email Testing · Vendor site 2026-10-04

MailCatcher runs a simple local SMTP server that captures outbound mail and displays it in a web inbox for development and QA. It shows HTML, plain text, and source views, supports attachments, and integrates with frameworks via SMTP or catchmail.

Updated 2026-10-04View sources

Official website

Category: Email Testing
Free access: Open source Ruby gem (latest 0.10.0 noted on site) installable via gem install mailcatcher at no listed fee.
API access: SMTP listener on localhost plus a web UI; Rails and PHP docs show configuring apps to deliver to the local MailCatcher SMTP port.

Is MailCatcher right for you?

A good fit for

Developers testing email flows locally without sending messages to real recipients.

Before you choose

Project README-style site warns against adding mailcatcher to Gemfile because of gem conflicts with application dependencies.

Dev SMTP sink

MailCatcher catches application email in a local SMTP server and web interface so teams can inspect messages during development.

What it can do

Features & capabilities

Unknown is different from unavailable. Each fact carries its own evidence.

Capability	Value	Evidence	Checked
Local SMTP capture	Site explains MailCatcher serves mail through smtp://127.0.0.1:1025 with UI at http://127.0.0.1:1080.	Facts sourced	2026-10-04
Message views	Features list HTML, plain text, and source versions plus attachment downloads.	Facts sourced	2026-10-04
Latest release	Homepage lists latest version 0.10.0 released 25 May 2024.	Facts sourced	2026-10-04

Understand the total cost

MailCatcher pricing & plans

Pricing

Not listed

Official monthly price not confirmed

API: SMTP listener on localhost plus a web UI; Rails and PHP docs show configuring apps to deliver to the local MailCatcher SMTP port.

Explore pricing & history

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The practical questions

Frequently asked questions

What is MailCatcher used for?

Does MailCatcher have a free plan?

Open source Ruby gem (latest 0.10.0 noted on site) installable via gem install mailcatcher at no listed fee.. This record does not confirm an ongoing free plan.

How much does MailCatcher cost?

A listed monthly price has not been confirmed. See the plan cards for entitlements, billing commitments and seat minimums.

Can I use MailCatcher through an API?

SMTP listener on localhost plus a web UI; Rails and PHP docs show configuring apps to deliver to the local MailCatcher SMTP port.. API access and subscription access may have different terms; consult the linked sources.

What should I check before choosing it?

Project README-style site warns against adding mailcatcher to Gemfile because of gem conflicts with application dependencies.

Price history

No retained pricing changes yet. A current price alone does not establish a historical trend.

How this profile is supported

Identity and profile

Reviewed vendor source

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2026-10-04

Facts apply to the named version and check date. Send a sourced correction if something changed.