▮ Unuploaded

Converter · No upload

JPG to PNG, privately

Drop in JPGs and download lossless PNGs. The conversion runs entirely inside your browser — nothing is uploaded, the network meter below proves it live, and it keeps working with your wifi switched off.

Statusidle Files— OutputPNG Network since file read—

How this converter works

Your browser already knows how to decode JPG — it does it on every web page. When you choose a file, the File API opens it in memory, the browser's own decoder turns it into raw pixels, those pixels are drawn onto a canvas inside this tab, and the canvas re-encodes them as a lossless PNG. The result is wrapped in a Blob and offered back as a download link. No step involves a network transfer, because the file is already on your machine and this site has no server to send it to.

The readout's network meter arms the instant your first file is read and counts every request the page makes from that moment — it stays at zero, in green. You can confirm it two stronger ways: watch your browser's developer-tools Network tab stay silent while you convert, or switch on airplane mode and convert anyway — after one visit this page is cached and works entirely offline. The methodology page walks through each verification.

The honest limits: conversion cannot restore detail that JPG compression already discarded — PNG makes your image lossless from here forward, not retroactively. File sizes grow, often several-fold on photographs, because lossless compression pays for what it keeps. And re-encoding strips EXIF metadata — GPS, camera model, timestamps — from the output, which most people sharing images consider a feature, but note the capture date first if you need it.

Frequently asked questions

Is my image uploaded anywhere?
No. Your browser decodes the JPG itself, redraws it on a canvas inside this tab, and re-encodes it as a PNG — all in memory, on your device. The readout's network meter counts every request from the moment your file is read and stays at zero, and the methodology page shows how to verify that independently.
Will converting to PNG improve the quality?
No — detail that JPG compression already discarded cannot be restored by any converter. What PNG gives you is lossless from here on: the pixels you have now will survive any number of further edits and saves without degrading further.
Why is the PNG so much bigger than my JPG?
PNG compresses without losing information, which costs space — especially on photographs, where JPG's lossy approach is extremely efficient. A several-fold size increase is normal for photos. PNG earns its keep on screenshots, diagrams, and text, where its compression is efficient and JPG's artifacts are most visible.
Does the PNG get transparency?
The format supports it, but your image won't gain any: JPG has no transparency, so there is none to carry over. Every pixel of the PNG is exactly as opaque as it was in the JPG. This tool converts formats — it doesn't remove backgrounds.
Is the photo's EXIF data kept?
No. Re-encoding through a canvas strips metadata — GPS location, camera model, timestamps — from the output. For images you're about to share, that's a privacy feature; if you need the capture date, note it before converting.

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