Compress Image
Reduce JPEG or WebP size with a visual quality control. Your files are never uploaded to our servers. ToolkitPoint processes them on your own computer, so confidential documents stay with you.
Processed in your browser. Your files are not uploaded.
How to use Compress Image
- Select or drop one or more files in "Select or Drop Images (JPG, PNG, WebP, AVIF)"; each gets a row with thumbnail, size and dimensions.
- Choose "Output Format": Keep Original, WebP, JPEG, lossless PNG, "PNG smaller (reduced colours, lossy)", or AVIF where your browser can write it.
- Drag the "Compression Quality" slider from 10 to 100 percent (default 80).
- Pick "Max Dimension (Optional)" from Original Resolution down to Web Display (800px), which scales the longer side.
- Optionally tick "Smart quality" (searches the lowest quality that meets an SSIM target) and keep "Never make it bigger" on. Press "Compress All Images", use "Compare" for a slider preview, then download per image or as a ZIP.
Worked example
Add a 4000 x 3000 photo named holiday.jpg, choose Convert to WebP, quality 80% and Full HD (1920px). The longer side becomes 1920 and the other is 3000 x 1920 / 4000 = 1440, so the result is 1920 x 1440 and is named holiday-compressed.webp. The row then shows the new size with a saving badge and a Compare button.
When to use this tool
- Shrinking a folder of phone photos to a web-friendly size before uploading them to a blog.
- Converting product PNGs to WebP for a faster shop page.
- Reducing a set of screenshots to 1280 pixels wide for a documentation page.
Important limitations
Lossy image compression discards imperceptible pixel data; already heavily compressed images may experience diminishing size returns without resizing.
Frequently asked questions
Is the compression really lossless?
No. JPEG, WebP and reduced-colour PNG outputs are lossy re-encodes; only the plain PNG option keeps every pixel (and it can be larger). Use Smart quality or a high value and check the Compare slider before replacing an original.
Why does the quality slider not change my PNG?
PNG output is lossless, and the browser ignores the quality value for it. Files shrink only through resizing or, when you switch format, by converting to WebP or JPEG. A PNG can even come out larger.
What happens to transparency and metadata?
Images are redrawn on a canvas, so EXIF such as GPS position and camera model is dropped from every re-encoded file, and the row tells you when a photo carried GPS. If the never-bigger guard keeps your original file, its bytes (and metadata) are unchanged. Transparent areas turn white for JPEG but survive in WebP and PNG.
How does resizing choose the new dimensions?
The longer side is set to the chosen maximum and the other side is scaled in proportion. An image already smaller than the limit is not enlarged.
What if I keep the original format with an AVIF?
Browsers can read AVIF but most cannot write the old format back, so Keep Original turns AVIF into WebP and says so; the file extension always matches the real data. AVIF output appears in the format list only when your browser can encode it.
What does the never-bigger guard do?
If the new file is not smaller than the original and the dimensions were not reduced, the tool keeps your original file instead and labels it, so a compressed copy is never larger than what you started with.