# jstedfast/MailKit

A cross-platform .NET library for IMAP, POP3, and SMTP.

Repository: https://github.com/jstedfast/MailKit
Canonical: https://ross.abutalabs.com/products/mailkit
Homepage: http://www.mimekit.net
Language: C#
License: MIT
License Family: permissive
Topics: c-sharp, email, mime, mime-parser, dkim, pgp, smime, smtp, imap, pop3, imap-client, pop3-client, smtp-client
Last push: 2026-08-19T17:49:32+00:00

## Health v2 (maintenance only)
Score: 76/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 98, release rhythm 35, longevity 100
- inputs: {"age_days": 4652, "days_push": 14, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6844, forks 866 (observed 2026-08-28T04:09:50.849052+00:00)

## What it is
MailKit is a cross-platform .NET mail client library built on top of MimeKit, providing IMAP, POP3, and SMTP support along with a high-performance MIME parser. It supports S/MIME, OpenPGP, DKIM, and ARC for secure email handling.

## Use cases
- send and receive email in a .NET application
- parse email messages from files or streams
- connect to an IMAP or POP3 mailbox from C#
- sign and encrypt email with S/MIME or OpenPGP
- verify DKIM signatures on incoming mail
- parse a Unix mbox file in C#
- build a cross-platform mobile email app

## When to choose
- you need robust, high-performance email handling in .NET
- you need IMAP/POP3/SMTP client functionality with MIME support
- you need email encryption, signing, or DKIM/ARC verification
- you need a library that runs on Windows, Linux, macOS, iOS, and Android

## When to avoid
- you need a mail server rather than a client library
- you are not on a .NET platform
- you only need simple SMTP sending and prefer a minimal dependency

## Facets
- artifact type: library
- maturity: stable
- function: email, parser, cryptography, http-client
- domain: email, developer-tools, security, cross-platform
- platform: dotnet, cross-platform, windows
- tags: mime, imap, smtp, pop3, dkim, smime, openpgp, c-sharp, linux, macos, android, ios

## Member repositories
- jstedfast/MailKit (main) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:50.849052+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 2026-08-29T17:41:51.097399+00:00, confidence not recorded.
  - readme: https://github.com/jstedfast/MailKit (fetched 2026-08-28T04:09:50.849052+00:00, sha 1fbc4e58ee96)
  - homepage: http://www.mimekit.net (fetched 2026-08-29T08:37:50.163962+00:00, sha d0244e6a4814)
  - site_page: https://mimekit.net/docs/html/Parsing-Messages.htm (fetched 2026-08-29T08:37:50.174690+00:00, sha e0ca0691ddc3)
  - site_page: https://mimekit.net/docs (fetched 2026-08-29T08:37:50.172931+00:00, sha a1b0716a5a55)
  - site_page: https://mimekit.net/docs/html/Working-With-SMime.htm (fetched 2026-08-29T08:37:50.176769+00:00, sha 403299079b12)
- Data as of 2026-08-30T08:39:29.467469+00:00.