Unuploaded

Converter · No upload

JPG to PNG, privately

Choose JPGs and download lossless PNGs. The browser handles both formats without an extra decoder download. Files are not uploaded, and the loaded tool works offline.

Statusidle Files— OutputPNG Network since file read—

Undecodable JPGs fail, with browser reasons where available; images beyond canvas capacity fail rather than saving smaller. One PNG per file, written back as 8-bit sRGB pixels: nothing JPG compression discarded comes back, the file usually grows, several-fold on photographs, EXIF, GPS and timestamps are removed, and an embedded colour profile is not carried. Takes .jpg and .jpeg.

The sample is a 240×120 JPG generated in this tab. PNG encoding avoids another lossy compression step, but it cannot restore detail lost in the JPG or remove the decode/canvas path's colour limits. Compare the actual input and output sizes.

How this converter works

The browser reads the selected JPG into memory and decodes it into pixels. A canvas then encodes those pixels as a lossless PNG, which the page offers as a Blob download. No extra library or network transfer is needed to convert the file.

Open your browser's developer tools with F12, select the Network tab and run a conversion. Check whether it creates any requests. JPG and PNG conversion uses the browser's built-in capabilities, so this tool has no decoder or encoder download to account for. The methodology page describes two other checks and the limits of the site's own meter.

Converting to PNG cannot recover detail lost during JPG compression. It prevents further lossy compression at this step, but file sizes usually grow, often several-fold for photographs. The output contains 8-bit sRGB pixels; embedded colour profiles and EXIF metadata, including GPS, camera model and timestamps, are not carried over. Note the capture date before converting if you need it. If the browser cannot decode the JPG, the tool reports a failure with the browser's reason where available. Images that exceed the browser's canvas limit also fail rather than being saved at a smaller size.

Frequently asked questions

Is my image uploaded anywhere?
No. The browser decodes the JPG, redraws it on canvas and encodes PNG locally. The meter counts resource-timing entries after the first file read, excluding earlier loads and WebSocket traffic. The methodology page explains the separate network-panel and offline checks.
Will converting to PNG improve the quality?
No. PNG does not restore detail already discarded by JPG encoding. It lets you encode the resulting pixels without another lossy compression step, but later editing, resampling or colour conversion can still change them. Retain the best original.
Why is the PNG so much bigger than my JPG?
Photographic detail and sensor noise often compress less compactly as lossless PNG than as lossy JPG, so output can grow several-fold. Size still depends on the image. PNG can be a useful choice for sharp text, screenshots and diagrams when avoiding compression artefacts matters.
Does the PNG get transparency?
No background is removed. Ordinary JPG input has no alpha channel, so this conversion produces an opaque PNG. PNG supports transparency, but a format change alone does not create it.
Is the photo's EXIF data kept?
The canvas conversion does not copy the JPG’s source EXIF, including GPS, camera model and capture timestamps. The PNG encoder can still write its own format metadata. Save original metadata you need before converting.

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