Image Compressor

What this tool does

The Image Compressor reduces the file size of your photos and graphics without sending them to a server. You choose a quality level, an optional maximum width, and an output format; click Compress; and the tool encodes the result in your browser using the open-source browser-image-compression library. You see the original size, the compressed size, and the percentage saved, plus a side-by-side preview so you can check whether the visual quality is acceptable before you download.

Why you might need it

Large image files slow down web pages, push email attachments over limits, and fill up device storage faster than necessary. A hero image that is 4 MB when it comes off the camera can usually be trimmed to under 200 KB without any visible quality loss, which can cut page load times in half for visitors on mobile connections. Ecommerce product galleries, blog posts, portfolio sites, and social media posts all benefit from smaller images: search engines factor page speed into rankings, and platforms like Instagram and Twitter recompress anything you upload anyway, so starting from a well-compressed file gives the algorithm a head start.

For document scans, compressing to JPEG or WebP at 80% keeps the text legible while making the file small enough to email. For profile pictures and logos, PNG at a reduced resolution is usually better than JPEG because it keeps edges sharp.

Compressing PNG files

PNG compression is a special case because PNG itself is already lossless — its encoder cannot make the file smaller without losing pixel-perfect fidelity. The biggest wins on a PNG photo come from re-encoding as JPEG or WebP, which can shrink a 4 MB photographic PNG down to 200–400 KB at quality 80 with no visible loss. For PNG illustrations with text, icons or hard edges, keep the output as PNG and shrink the dimensions with the max-width control instead — that gives the largest size reduction while keeping every line sharp. If you only need to strip PNG metadata (EXIF, colour profiles, embedded comments), the compressor re-encodes the file from scratch and discards any metadata that does not survive a clean canvas round-trip.

How to use it

1. Drop your image onto the dropzone, or click to browse for a file.
2. Adjust the Quality slider — try 80% to start.
3. Optionally set a Max width if you also want to shrink the image dimensions; leave it empty to keep the original size.
4. Choose an Output format: keep the original, or re-encode as JPEG (smallest for photos), WebP (modern, well-supported), or PNG (lossless).
5. Click Compress and wait for the busy indicator to finish.
6. Check the ”% smaller” figure and the preview. If the result looks good, click Download.

Format and quality notes

JPEG is the safe universal choice for photographs — it is supported everywhere and compresses photos efficiently. Its main drawback is that it discards the alpha channel, so a transparent logo exported as JPEG will have a white or black background. WebP is a newer format that achieves similar or better quality at smaller sizes and does support transparency; the only caveat is that very old browser versions (pre-2020) do not support it, though this is rarely a concern today. AVIF and PNG are also available as input formats but are not selectable as output targets in the compressor — use the Image Format Converter for those.

The quality slider controls how aggressively the encoder discards information. Values below 60% start to introduce visible blocking and colour banding in photographs. Values above 90% produce files that are barely smaller than the original. The sweet spot for web delivery is 75–85%.

Tips for best results

Start with the highest quality input you have. Compressing an already-compressed JPEG degrades quality faster than compressing the original raw or TIFF. If you need the image for multiple uses (a full-size version for print and a small version for a thumbnail), compress each separately from the original rather than compressing the compressed version a second time.

Use the max-width cap to kill two birds with one stone: if your layout never renders an image wider than 1200 px, there is no point uploading a 4000 px original. Set max width to 1200 and let the compressor handle the downscale as part of the same step. For next-generation format comparison, use this tool alongside the Image Format Converter to see whether WebP or JPEG is the better fit for a particular image.