Resize Image To Exact KB — Free Online Image Compressor

Compress any photo to a precise file size in kilobytes. Type the exact KB you need — 20, 35, 50, 75, 100, 150, 200 or any custom value — and the tool shrinks your JPG, PNG or WebP right in the browser while protecting quality, text and detail.

What is this tool?

Resize Image To Exact KB is a free, universal image compressor that lets you target a specific file size measured in kilobytes instead of guessing at a quality slider. Whether a form demands a photo under 50KB, a website needs lightweight images, or an upload portal caps files at a fixed size, you enter the number and the tool does the rest. It runs 100% in your browser, supports JPG, JPEG, PNG and WebP, and never uploads your picture to any server, so your files stay private on your own device.

Because the compressor measures the encoded size after every attempt, the number you see is the real file size you will download — there is no guesswork. Photographs with smooth gradients compress further than busy images full of fine texture, so if you need an aggressive target, a cleaner background helps. For text-heavy graphics such as YouTube thumbnails or posters, keeping the original resolution and letting the quality search do the work usually preserves sharper edges than shrinking the image yourself beforehand.

How it works

1. Upload a JPG, JPEG, PNG or WebP image by dragging it onto the box or tapping to browse — on mobile you can pick straight from your camera roll.
2. The tool reads the original file size and dimensions, then runs a smart compression pass entirely inside your browser.
3. It lowers the encoder quality gradually first, and only reduces the pixel dimensions if that is the only way to reach your target — so text, logos and faces stay sharp.
4. Preview the before-and-after side by side, check the final size and reduction percentage, then download your image. Nothing is ever uploaded to a server.

Benefits

• Hit any exact target — 20KB, 50KB, 100KB, 200KB or a fully custom value you type yourself.
• Quality-first compression keeps thumbnails, posters, logos and text crisp.
• Works on JPG, JPEG, PNG and WebP, with optional JPG / PNG / WebP output.
• Completely free with no sign-up, no watermark and no upload limits.
• Private by design — all processing happens locally in your browser.
• Mobile-friendly: upload from your phone's gallery or camera and download instantly.

Features

• Custom KB input plus one-tap presets for the most common sizes.
• Live before vs after preview with original and final dimensions.
• Real-time compression progress bar and final size + reduction percentage.
• Smart engine that lowers quality before ever touching resolution.
• Download, re-compress and 'compress another image' controls.

Step-by-step guide

1. Open the tool and choose (or confirm) your target size in KB.
2. Drag and drop your image, or tap the box to upload from your device.
3. Press the Compress button and watch the live progress bar.
4. Compare the before/after preview and the final file size.
5. Click Download to save the compressed image, or compress another.

Frequently asked questions

How do I resize an image to an exact size in KB?

Type your target into the Custom field (or pick a preset), drop in your JPG, PNG or WebP image, and press Compress. The tool searches for the highest quality that fits your KB target and shows the final size instantly.

Which file formats are supported?

You can upload JPG, JPEG, PNG and WebP images, and download the result as JPG, WebP or lossless PNG.

Will compressing reduce my image quality?

The engine is built to preserve quality. It reduces encoder quality gradually and only shrinks dimensions when absolutely necessary, so text and detail stay readable. Very small targets (like 20KB) on large images may still soften slightly.

Is the exact KB always guaranteed?

We aim to get as close as possible without going over while keeping the image clear. For tiny targets the result may land a little above the number rather than ruining quality — for example around 18–22KB for a 20KB target.

Are my images uploaded to a server?

No. All compression runs locally in your browser using the HTML canvas, so your images never leave your device.

Is this tool really free?

Yes, completely free with no account, no watermark and no limit on how many images you can compress.