# premailer/premailer

Preflight for HTML email

Repository: https://github.com/premailer/premailer
Canonical: https://ross.abutalabs.com/products/premailer
Homepage: https://premailer.github.io/premailer
Language: Ruby
License: NOASSERTION
License Family: other
Topics: premailer, nokogiri, css, ruby, mail, inline
Last push: 2026-08-19T16:58:24+00:00

## Health v2 (maintenance only)
Score: 76/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 98, release rhythm 35, longevity 100
- inputs: {"age_days": 6124, "days_push": 14, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2416, forks 361 (observed 2026-08-28T04:06:50.315691+00:00)

## What it is
Premailer is a Ruby gem that prepares HTML email for delivery by inlining CSS styles, converting relative URLs to absolute, and checking CSS properties against email client support. It can also generate a plain-text version of the email and report potentially problematic CSS.

## Use cases
- inline css styles into html emails
- convert a newsletter html file to email-safe html
- generate plain text version of an html email
- check which css properties are unsupported by email clients
- convert relative links and image paths to absolute urls in email html

## When to choose
- you send HTML email from Ruby and need inline CSS for client compatibility
- you want automated warnings about email-client-unsupported CSS
- you need a plain-text alternative generated from HTML email

## When to avoid
- you need email sending/delivery itself - this only transforms HTML
- your project is not in Ruby
- you need MJML-style component-based email templating

## Facets
- artifact type: library
- maturity: active
- function: templating, email, parser, css-framework
- domain: email, web-development, developer-tools
- platform: ruby, cli
- tags: html-email, css-inlining, email-compatibility, plain-text-generation, nokogiri

## Member repositories
- premailer/premailer (main) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:50.315691+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:33:09.610799+00:00, confidence not recorded.
  - readme: https://github.com/premailer/premailer (fetched 2026-08-28T04:06:50.315691+00:00, sha cbc0b72cf11b)
  - homepage: https://premailer.github.io/premailer (fetched 2026-08-29T10:13:43.512653+00:00, sha 9dd52e1977ef)
- Data as of 2026-08-30T08:39:29.467469+00:00.