How do I compress an image with img-tools?

Drag and drop your image onto the upload zone (or click to browse, or paste with Ctrl+V / Cmd+V), then pick an output format — JPEG, PNG, or WebP — and adjust the quality slider, or enter a target size in KB to let it find the best fit. Click Download to save the result. It is completely free and runs entirely in your browser via the Canvas API, so your image is never uploaded.

Are images uploaded to a server?

No. All processing runs entirely in your browser; images never leave your device. This is the core design principle of the tool.

Is compressing and converting images free?

Yes — compressing JPEG, PNG, and WebP images (or converting between formats) is completely free, forever. No account, no sign-up, and no limit on the number of images you compress. All processing uses the Canvas API in your browser; your images are never uploaded to any server. The site is ad-supported.

Does it work offline?

Yes. The tool uses the Canvas API with WebGL2 (Canvas 2D fallback) and requires no server connection. Disconnect after loading the page and it still works.

What image formats are supported?

Input: JPEG, PNG, WebP, AVIF (browser-decoded). Output: JPEG, PNG, WebP. For AVIF output, use the dedicated JPG to AVIF converter — it is already available.

Is there a file size limit?

No artificial limit. The practical limit is your device's available memory (typically tens of MB or more). Very large images may take longer to process.

Why is there no quality option for PNG?

PNG is a lossless format; the browser's canvas.toBlob does not accept a quality parameter for PNG, so the quality slider and target KB field are automatically disabled.

How does "compress to target KB" work?

The tool performs a binary search over JPEG or WebP quality values and finds the highest quality that fits within your target size in 1–8 iterations, entirely in the browser.

What is the output quality like?

Encoding uses the browser's native Canvas API; quality matches each browser's implementation. For JPEG and WebP, you can precisely control output quality via the quality slider.

Image Compress & Convert

Compress Image is a free browser-based tool that reduces JPEG, PNG, and WebP file size or converts between formats with no upload required. Set a target file size in KB for JPEG/WebP and the tool binary-searches the optimal quality in under 8 iterations. Processing uses the Canvas API entirely on your device — no server, no account, works offline.

Compress and convert JPEG, PNG, WebP images directly in your browser — free, no upload required.

100% Free — Forever. No fees, ever.
Private: files are processed locally in your browser and never sent to a server.
No upload, no account, no sign-up.

Open the tool
Go to the Compress & Convert page. No sign-up or installation required.
Load your image
Drag and drop an image onto the upload zone, click to browse, or paste with Ctrl+V / Cmd+V.
Choose output format and quality
Select JPEG, PNG, or WebP from the export dialog. For JPEG and WebP, adjust the quality slider (1–100). For PNG, lossless compression is used automatically.
Set a target file size (optional)
Enter a target size in KB for JPEG or WebP. The tool performs a binary search to find the highest quality that fits within your target.
Download
Click Download. Your compressed or converted image is saved directly to your device.

How do I compress an image with img-tools?: Drag and drop your image onto the upload zone (or click to browse, or paste with Ctrl+V / Cmd+V), then pick an output format — JPEG, PNG, or WebP — and adjust the quality slider, or enter a target size in KB to let it find the best fit. Click Download to save the result. It is completely free and runs entirely in your browser via the Canvas API, so your image is never uploaded.
Are images uploaded to a server?: No. All processing runs entirely in your browser; images never leave your device. This is the core design principle of the tool.
Is compressing and converting images free?: Yes — compressing JPEG, PNG, and WebP images (or converting between formats) is completely free, forever. No account, no sign-up, and no limit on the number of images you compress. All processing uses the Canvas API in your browser; your images are never uploaded to any server. The site is ad-supported.
Does it work offline?: Yes. The tool uses the Canvas API with WebGL2 (Canvas 2D fallback) and requires no server connection. Disconnect after loading the page and it still works.
What image formats are supported?: Input: JPEG, PNG, WebP, AVIF (browser-decoded). Output: JPEG, PNG, WebP. For AVIF output, use the dedicated JPG to AVIF converter — it is already available.
Is there a file size limit?: No artificial limit. The practical limit is your device's available memory (typically tens of MB or more). Very large images may take longer to process.
Why is there no quality option for PNG?: PNG is a lossless format; the browser's canvas.toBlob does not accept a quality parameter for PNG, so the quality slider and target KB field are automatically disabled.
How does "compress to target KB" work?: The tool performs a binary search over JPEG or WebP quality values and finds the highest quality that fits within your target size in 1–8 iterations, entirely in the browser.
What is the output quality like?: Encoding uses the browser's native Canvas API; quality matches each browser's implementation. For JPEG and WebP, you can precisely control output quality via the quality slider.

WebP achieves 25–35% smaller files than JPEG at equivalent visual quality — source: Google WebP study (developers.google.com/speed/webp/docs/webp_study).
PNG uses DEFLATE lossless compression (RFC 1951), making it ideal for screenshots and icons that require pixel-perfect reproduction.
JPEG uses Discrete Cosine Transform (DCT) lossy compression; quality 75–85 is the accepted sweet spot for most web use cases.
The Canvas API toBlob() method is specified by the W3C HTML Living Standard and is supported in all modern browsers (Chrome, Firefox, Safari, Edge).
Client-side processing eliminates network round-trip latency, making browser-based compression typically 10x faster than cloud services for typical image sizes.

📦 Image Compress & Convert

Image Compress & Convert