About ConvertSamurai
ConvertSamurai is a free online image converter built around a simple idea: the fastest, most private way to convert an image is in your own browser.
Why we built it
Most image converters online follow the same pattern — upload your file to a server, wait for it to process, then download the result. That model has three problems:
- It's slow. You wait for an upload, then a queue, then a download. For a single image you wanted to convert in two seconds, the round trip takes thirty.
- It's a privacy risk. Your photos, screenshots, design files, and personal documents end up sitting on someone else's server. Even with the best intentions, that's a leak waiting to happen.
- It costs money to run. Server-side conversion needs CPU, bandwidth, and storage. That cost gets passed on to users in the form of paywalls, watermarks, file size limits, and ads on top of ads.
Modern browsers can do all of this work locally. They have hardware-accelerated decoding for most formats, native encoders for PNG, JPEG, WEBP, and AVIF, and enough JavaScript performance to handle TIFF, HEIC, BMP, and ICO through small specialized libraries. Once we realized this, the path was obvious.
How it works
When you drop a file into ConvertSamurai, three things happen — all on your device:
- The file is read into memory by your browser.
- It's decoded into raw pixel data using either the browser's built-in image APIs or, for less common formats, a small JavaScript decoder we load on demand.
- The pixel data is re-encoded into your chosen output format and offered as a download.
No part of this round trip touches our servers. We could shut down our website tomorrow and the conversion would still work for users who already had the page loaded.
What we support
Right now, ConvertSamurai handles ten image formats: PNG, JPG, WEBP, GIF, BMP, TIFF, SVG, AVIF, HEIC, and ICO. With every format able to convert to every other format, that's over 90 conversion paths in a single tool.
How we make money
ConvertSamurai is supported by display advertising. We chose the ad-supported model deliberately because it lets the tool stay completely free, with no signup wall, no premium tier, and no artificial limits. We try to keep ads non-intrusive and limited to a few well-defined slots.
That's the whole business model: a fast, free converter, paid for by ads, built once, used by anyone, on any device, in any browser.
The name
A samurai's sword is fast, precise, and respected for what it doesn't do as much as for what it does. We thought it was a fitting metaphor for a tool that does one thing well, gets out of the way, and never touches your files. The little kabuto helmet in our logo is a nod to that — focused, alert, and ready to cut.
Get in touch
Questions, suggestions, or bug reports — we'd love to hear from you. Drop us a line via the contact page.