Image Compressor
Compress JPG, PNG and WebP images in your browser at a quality you choose - nothing is uploaded.
How to use it
- Drop images onto the box, or click to choose several at once.
- Pick an output format. WebP is usually smallest; "keep original" re-encodes in the same format.
- Set the quality - around 80% is a good balance for photos.
- Download each result. The table shows the size saved.
What it does, and what it does not
It does: re-encode images at your chosen quality and format using your browser's canvas, showing before and after sizes so you can see the saving. It handles batches.
It does not: upload anything - every image stays on your device. For very large batches, do them in groups so your browser stays responsive.
Reference
Image weight is the single biggest cause of slow pages, and slow pages cost you rankings and conversions. Core Web Vitals - the loading and stability metrics Google measures - are dominated by images more than any other resource. Compressing your images before they go live is one of the highest-return, lowest-effort performance wins available, and this tool does it without sending your files to a server.
There are two kinds of saving. Re-encoding at a sensible quality throws away visual detail the eye barely notices: a photo saved at 100% quality is usually indistinguishable from the same photo at 80%, but often half the size. Switching format saves again - modern formats like WebP compress far better than the older JPEG and PNG for most images. This tool lets you do both: choose a target format and a quality level, and it re-encodes locally through the browser canvas. For photographs, JPEG or WebP at around 80% is the sweet spot. For graphics with flat colour or transparency, PNG or WebP is better. PNG stays lossless, so the quality slider does not apply to it.
A few habits multiply the benefit. Resize before you compress: serving a 4000-pixel photo into a 800-pixel slot wastes most of the file, so scale images to the largest size they actually display. Compress every image in your pipeline, not just hero images - the cumulative weight of product thumbnails and icons adds up. And once images are lean, help the browser further with width and height attributes to prevent layout shift, and lazy-loading for anything below the fold. Because this tool runs entirely in your browser, you can compress client images, unreleased product shots or anything sensitive without it ever leaving your machine - which is not something you can safely say about most free online compressors.
Questions
Which format should I choose?
WebP is usually the smallest for both photos and graphics and is supported everywhere that matters now. Use JPEG for broad compatibility on photos, and PNG or WebP when you need transparency. PNG is lossless, so quality does not apply.
What quality setting is best?
Around 80% for photos is usually indistinguishable from the original at roughly half the size. Drop lower for thumbnails, go higher for hero images where detail matters.
Are my images uploaded?
No. Everything is processed in your browser with the canvas API. Your images never leave your device, so this is safe for client or unreleased work.
Should I resize as well as compress?
Yes, and it matters more. Scale images to the largest size they actually display before compressing - serving a huge image into a small slot wastes most of the file.
Does image size affect SEO?
Yes, through page speed and Core Web Vitals, which are ranking signals. Lighter images load faster, which helps both rankings and conversions.