Image Compressor & Converter
Compress, resize and convert JPEG, PNG, WebP and AVIF images — free, no sign-up, no watermark. Everything is processed inside your browser, so your images are never uploaded anywhere.
Drop images here
or click to browse · JPEG, PNG, WEBP, AVIF · up to 20 MB each
0 / 5 in this batch · images stay on your device
Each image is decoded with createImageBitmap and re-encoded on your own device. Your files are never uploaded, stored or transmitted — the tab holds them in memory and forgets them when you close it.
FYI: what this tool tracks (and what it never sees)▾
Your images never leave this tab. Compression runs locally, and the picture itself — pixels, file data, thumbnails — is never sent anywhere.
What we do collect (anonymous counts):
- That you opened the tool, and which image formats your browser can write
- How many images you added to a batch and which format you picked
- Per image: input and output format, byte sizes, savings percentage, how long it took
- Whether the Web Worker or the main thread did the encoding
- Button usage: downloads, ZIP exports, comparison opens, setting changes
- Failures, with any file name stripped out before it is sent
What we never collect:
- Your images — no upload, no thumbnails, no image data of any kind
- File names, folder names or paths
- Anything inside your files, including EXIF, GPS or camera data
- Account details — there are no accounts to collect them for
The counts go to the same Google Analytics property the rest of flavglen.dev uses, which also records standard page data (URL, device and browser, approximate location). Blocking Google Analytics with an ad or script blocker blocks all of it — the tool works exactly the same either way.
Keep the source format when the browser can re-encode it. Formats your browser cannot write are disabled, and any request still falls back to WebP or JPEG with a note on the result card.
0.30 – 1.00 · default 0.80. Lower values mean smaller files.
Aspect ratio is always preserved and smaller images are never enlarged.
Sources above 40 megapixels are scaled down before they reach the canvas, so an 8K panorama cannot exhaust your tab's memory.
Re-encoding through a canvas drops EXIF metadata — GPS coordinates, camera model and timestamps are stripped with it. JPEG cannot store transparency, so alpha is flattened onto white.
Images
0/0
Original
0 B
Optimised
0 B
Saved
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Nothing queued yet. Drop images above and they are optimised one after another — the original is kept in memory for the before/after comparison.
Drop up to 5 images at once. Two are encoded in parallel inside a Web Worker, so the page stays responsive, and every finished file can be downloaded on its own or as a single .zip archive.
Decoding happens with createImageBitmap, resizing and re-encoding on an HTML canvas. Your photos never touch a server, a queue or a log — there is nothing to clean up afterwards.
Convert between JPEG, PNG, WebP and AVIF, dial the quality from 0.30 to 1.00, and cap the width or height. Aspect ratio is preserved and images are never enlarged.
Are my images uploaded to a server?
No. Your images are read with the browser's own file API, decoded with createImageBitmap and re-encoded on an HTML canvas inside a Web Worker. The images themselves — pixels and file data — are never transmitted or stored, and closing the tab erases them. The only thing sent is anonymous usage counts (batch sizes, formats, byte sizes, savings) with file names stripped out, to the same Google Analytics property the rest of this site uses. The tool has an inline “FYI: what this tool tracks” note that lists exactly what is collected.
Which formats can I convert between?
JPEG, PNG, WebP and AVIF. The tool probes what your browser can actually encode: if AVIF is unavailable (many browsers cannot write it yet) the chip is disabled and any AVIF request gracefully falls back to WebP or JPEG, with a note on the result card telling you what was produced.
Is there a file size or batch limit?
Up to 20 MB per image and 5 images per batch — ideal for photos, screenshots and web assets. Sources above 40 megapixels are downscaled automatically before they reach the canvas, so even an 8K panorama cannot exhaust your tab's memory.
Does compressing remove EXIF metadata?
Yes. Re-encoding through a canvas strips EXIF data — GPS coordinates, camera model and timestamps are dropped with it, which is usually exactly what you want before publishing an image. Note that JPEG cannot store transparency, so alpha is flattened onto a white background.
Why did my PNG get bigger instead of smaller?
PNG is a lossless format, so converting a JPEG to PNG usually increases the file size. For smaller output keep the source format, use WebP, or lower the quality slider — and resize large images, which is where the biggest savings come from.