About This Site
JFIF Converter is an independent web-tools project that builds free image converters which run entirely inside the browser. No files are uploaded, no accounts exist, and the site is funded by advertising rather than by charging for conversions.
Why this site exists
Millions of people run into a .jfif file for the first time when a photo they downloaded refuses to open, refuses to upload, or refuses to print. The answer is simple — it is a JPEG with an unusual extension — but finding that answer usually means wading through a converter that wants an email address, or an article that spends four hundred words restating the question.
So this site does two things and no others: it converts the file immediately, and it explains the format accurately. Both for free, both without asking for anything.
Who publishes it
JFIF Converter is an independent project run by a small team of web developers. We are not affiliated with Adobe, Google, Microsoft, the Joint Photographic Experts Group or any standards body, and we do not accept payment for coverage, placement or links.
We publish under a brand rather than an individual byline because the work here is engineering rather than opinion: format claims are verifiable against a published specification, and converter behaviour is verifiable by running it. Everything on this site is intended to be checkable without taking our word for it. Where we state a technical fact, we cite the standard it comes from. Where we describe conversion behaviour, you can reproduce it in your own browser's developer tools in under a minute.
Corrections and questions reach a human at [email protected]. Our editorial and testing policy sets out how claims get verified and how errors get fixed.
How the tools are built
Every converter on this site is plain JavaScript running in your browser. There is no upload endpoint, no processing server and no third-party conversion API. Image decoding uses the browser's own createImageBitmap() and canvas; PNG, JPEG and WebP encoding uses canvas.toBlob().
The BMP, ICO, ZIP and PDF writers are our own code, about three hundred lines in total, written specifically so the site does not have to load a third-party library. That has two consequences worth stating plainly: the page loads faster, and there is no external script with the ability to read your files.
For JFIF to JPG and JFIF to PDF the image is never decoded at all — the compressed JPEG stream is copied directly, which is why those conversions are exactly lossless rather than approximately lossless.
How the site is funded
Advertising, and nothing else. There is no paid tier, no affiliate marketing, no sponsored content and no data sold to anyone. We do not know what your images contain, because they never reach us.
Ads are the reason the tools can be genuinely unlimited: serving a page costs us a fraction of a cent, while converting a hundred large images on a server would not be. Because the work happens on your device, we can afford to remove every cap that server-based converters need in order to survive.
Privacy, in one sentence
Your image files are never transmitted anywhere, because the code that would transmit them does not exist on this site. The full privacy policy covers analytics and advertising cookies, which are the only data the site touches at all.
What we will and will not add
We will add formats people actually ask for, and we will keep the guides current as browsers and specifications change. We will not add an account system, an upload queue, a paid tier or a "download our desktop app" banner. If a feature would require your file to leave your device, it does not get built.