Put a JPG into a lossless container so no further quality is lost — and know exactly what that does not fix.
Your files never leave your browser — all processing is local.
✓ EXIF, GPS and all other metadata are removed from the output.
Drop images here
or click to browse — PNG, JPEG, WebP, GIF, HEIC, AVIF, SVG — you can also paste images (Ctrl+V) anywhere on this page
From the conversion onward nothing more is thrown away: the output records every pixel the decoder produced, so you can re-save it as often as you like without further degradation. That is the only guarantee on offer. Nothing the original encoder already discarded comes back. Block edges at 8 × 8 boundaries, the ringing halo around high-contrast text and the color detail lost to 4:2:0 subsampling are all recorded faithfully, as if they were the subject of the photograph, and they are now permanent in a way they were not before — a higher-quality re-encode could at least have been redone from the source.
Converting also cannot create an alpha channel. The input is fully opaque, so the output is fully opaque; the white or checkered area behind a logo stays as solid pixels. Removing a background is an editing job, not a format job, and the common advice to convert a photo so the background becomes transparent is simply wrong. Metadata follows the same rule as every other route here: the EXIF block and the ICC profile are not copied, so dates, GPS and the camera's color description do not survive, while EXIF orientation is applied to the pixels before encoding so the picture is never left sideways.
One consequence catches people out. Compression artifacts are noise, and noise is the worst case for PNG's compressor, which works by predicting each pixel from its neighbours. A heavily compressed input can produce a larger output than a clean one of the same subject, because the very artifacts you dislike are expensive to store losslessly. The "optimize (oxipng)" checkbox — off by default on this page — runs oxipng at level 2 over the result, which recovers some of that by choosing better row filters and reducing the color type where it can.
The 2026-09-12 measurement started from a 1280 × 854 JPG at quality 85, 351,967 bytes. Decoding it and writing PNG with "optimize (oxipng)" on gave 1,880,440 bytes — about 5.3 times the input. That checkbox is off by default; leave it off and the browser's PNG encoder is usually a little larger still. Nothing about the picture improved in exchange for those bytes; they pay for storing an approximation exactly. Expect a bigger multiplier for noisy, detailed or heavily compressed photographs, and a much smaller one for flat graphics, where row filters and palette reduction work well and the result can come surprisingly close to the input size.
Never do this for the web: you multiply the bytes without adding a single pixel of quality, and both WebP and AVIF would have gone the other way. Do not do it for archiving either — the result is not more faithful to the scene than the file it came from, it is only bigger, and it has lost the EXIF an archive would be indexed by. Do not do it expecting a transparent background or sharper text. The good reasons are narrow and real: a tool, template or upload form that accepts PNG only, an image you are about to edit through several rounds of saving, or a screenshot you want to annotate without each save costing quality.
Conversion happens entirely in your browser — no upload, no queue, no watermark. Drop in as many files as you like and download them individually or as a zip.
No. The blocking, ringing and colour smearing are already in the decoded pixels, and a lossless format records them exactly. What you gain is that no further artifacts are added on later saves. Repairing the existing ones needs an editor, or the original file.
Lossy compression stored an approximation in a few hundred kilobytes; lossless compression has to store every pixel of that approximation exactly, including its artifacts, which are noisy and resist prediction. In the measured sample 351,967 bytes became 1,880,440, with "optimize (oxipng)" on; this page leaves that checkbox off by default.
No. The source has no transparency to carry over, so the output is fully opaque and the background stays as solid pixels. PNG only makes transparency possible; creating it means selecting and erasing the background in an image editor first.
No. Conversion happens inside your browser using the canvas API and a Web Worker — files never leave your device. There is no upload step, no queue and no file size limit beyond your machine's memory.
No — and that's a feature. Re-encoding through the canvas strips all metadata: GPS location, camera model, timestamps and color profiles. The output contains pixels only, which is usually what you want before sharing an image publicly.
Yes. Drop or paste any number of files; each is converted in the background with its own progress and download button, and you can grab everything at once as a .zip archive.
It depends on the target. The converter always decodes to raw pixels and re-encodes, whichever formats are involved, which is also how metadata gets stripped. For lossless targets (PNG, and GIF within its 256-color limit) the pixels stay identical to what was decoded; for JPEG, WebP and AVIF the quality slider controls the trade-off, and converting a file that is already lossy adds one more generation of loss.