Stalwart mail-parser

At a glance

• Editor score
  6.3 / 10
• Pricing
  Open source
• Best for
  Low-level email parsing libraries
• Paid from
  Free
• Attachment parsing
  Yes
• Facts checked
  20 Sep 2026

• Where it wins

  • Parses RFC 5322/RFC 822 messages, MIME parts, headers, and bodies
  • Extracts attachments, including nested messages, with zero-copy string handling
  • Supports 41 character sets plus optional Serde and rkyv integration

• Where it doesn't

  • Requires Rust integration rather than a hosted email-parsing service
  • Does not provide a webhook or workflow layer for processing email
  • Focused on parsing rather than OCR or custom extraction fields

Our verdict on Stalwart mail-parser

Stalwart mail-parser is an open-source Rust library for developers embedding email parsing into applications. It handles RFC 5322 and RFC 822 messages, MIME bodies and headers, addresses, dates, message IDs, received headers, text and HTML bodies, MIME parts, nested messages, and attachments. The library is used by Stalwart Mail Server and is aimed at teams that need a parsing component inside their own Rust-based systems rather than a hosted email-processing product.

Its strongest area is low-level message coverage. Attachment extraction includes nested messages, while configurable header parsing and ignored headers give developers control over how messages are interpreted. Text and HTML body extraction includes automatic alternative conversion when one format is missing. Support for 41 character sets, with additional optional encodings, helps with varied message content. Zero-copy string handling is also included for applications where parsing efficiency and memory handling matter.

The open-source model keeps Stalwart mail-parser oriented toward implementation work rather than plan selection or managed operations. Optional Serde and rkyv integration can help it fit applications that already use those Rust serialization ecosystems. The tradeoff is scope: this is a library-level component, not a hosted service with a broader email automation layer. Choose it when your team needs detailed RFC and MIME parsing, nested attachment handling, and Rust integration. Choose another category option when the priority is a ready-to-connect API, webhooks, workflows, OCR, or configurable extraction fields.

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Stalwart mail-parser pricing

Stalwart mail-parser fact sheet

Alternatives to Stalwart mail-parser

• AirparserA flexible email and document parser for structured extraction and review workflows.8.7
• DigiParserA practical parser for turning email attachments and documents into structured, exportable data.8.5
• MailparserA broad email parsing service for turning recurring messages into structured workflows.8.2

See all Stalwart mail-parser alternatives →

Featured on iTechGuides

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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

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Last updated 7 Oct 2026 · How we research and update