What Is a .fbs File? .fbs Format, MIME & How to Open

Quick facts

Extension.fbs

File typeFBS Image

MIME typeimage/vnd.fastbidsheet

CategoryImage

Charset—

Compressible—

What is .fbs

What is a .fbs file?

A .fbs file is a FBS Image. It is a raster or vector image format used for photos, web assets and design work.

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

Related entities: it maps to image/vnd.fastbidsheet and is used by FlatBuffers among others — and is delivered over HTTP via the Content-Type header.

How to open .fbs files

Use Photoshop or GIMP to open and edit .fbs 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: image/vnd.fastbidsheet

Common software that reads/writes .fbs:

PhotoshopGIMPPaintPreview

Relation chain

.fbsextension of

format

FBS Imageserved as

mime type

image/vnd.fastbidsheetsent via header

http header

Related extensions

Related MIME types

image/vnd.fastbidsheet

.fbs

Related programming languages

FlatBuffers

.fbs

Common uses

Web graphics and photos
Design assets and icons
Print and photography

How to edit .fbs files

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

How to create .fbs files

Create a new file and save it with the .fbs extension, or export this format from Photoshop.

Frequently asked questions

What programs can open .fbs files?

Common options include Photoshop, GIMP, Paint. You can also open many of these files with built-in viewers or a browser.

How do I create a .fbs file?

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

What is the relationship between .fbs and the image/vnd.fastbidsheet MIME type?

image/vnd.fastbidsheet is the media type identifier used for .fbs files during network transfer (for example in the HTTP Content-Type header).

Sources & standards

Updated 2026-08-18

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