BMP to AVIF

An AVIF file is an image saved in the AV1 Image File Format — a modern, highly compressed format used across the web. It holds the same kind of photo or graphic a JPG would, but at roughly half the file size. The catch: it's new enough that some older apps and devices can't open it yet, which is usually why you landed here. If you just downloaded an image and it saved as something ending in .avif that won't open, you're in the right place. This guide explains what the file is, why you're suddenly seeing them, and exactly how to open one on Windows, Mac, iPhone, Android, and Linux — plus the one fix that works everywhere.

BMP files are enormous. A single uncompressed bitmap image can be 10, 20, even 50 times larger than the equivalent JPG — with no visible quality advantage for most use cases. Sending a BMP by email, uploading it to a website, or sharing it on social media is slow, impractical, and in many cases simply impossible due to file size limits.

Image conversion online is the process of changing an image file from one format to another directly in your browser — no software to install, no account required. Transfonic supports 10 image formats, including JPG, PNG, WebP, HEIC, AVIF, GIF, BMP, TIFF, ICO, and SVG, converting between them in seconds for free.

This guide covers the full JPG vs JPEG story, when and why you might need to change between them, and how to convert your JPEG to other formats like WebP, BMP, TIFF, and SVG using Transfonic's free Image Conversion tool — no software, no signup required.