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.SIEVE·File Extension

SIEVE Data & Text — A .sieve file is a SIEVE Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.

Data & Textapplication/sieve

Quick facts

Extension.sieve

File typeSIEVE Data & Text

MIME typeapplication/sieve

CategoryData & Text

Charset—

Compressible—

What is .sieve

What is a .sieve file?

A .sieve file is a SIEVE Data & Text. It is a text-based data format widely used for configuration files, data interchange and API payloads.

In the mime-db registry it maps to application/sieve. When serving .sieve over HTTP, set the Content-Type header as shown in Developer info below.

Related entities: it maps to application/sieve and is used by Sieve among others — and is delivered over HTTP via the Content-Type header.

How to open .sieve files

Use VS Code or Notepad++ to open and edit .sieve files.
Any text editor (Notepad, VS Code) can inspect the raw content as text.

Developer info

When served over HTTP, responses should set the following header:

Content-Type: application/sieve

Common software that reads/writes .sieve:

VS CodeNotepad++Sublime Textjq

Relation chain

.sieveextension of

format

SIEVE Data & Textserved as

mime type

application/sievesent via header

http header

Related extensions

Related MIME types

Related programming languages

Sieve

.sieve

Common uses

Configuration files
Data interchange between systems
API request and response payloads
Logs and data exports

How to edit .sieve files

Open the file with VS Code, make your changes and save.
Most editors preserve the original formatting and encoding — avoid changing the charset.

How to create .sieve files

Create a new file and save it with the .sieve extension, or export this format from VS Code.

Frequently asked questions

What programs can open .sieve files?

Common options include VS Code, Notepad++, Sublime Text. You can also open many of these files with built-in viewers or a browser.

How do I create a .sieve file?

Create a new file in any text editor or the app that owns the format and save it with the .sieve extension.

What is the relationship between .sieve and the application/sieve MIME type?

application/sieve is the media type identifier used for .sieve files during network transfer (for example in the HTTP Content-Type header).

Sources & standards

Updated 2026-08-18

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