How do I resize an image to 20 KB?

Upload your photo, leave the target set to 20 KB, and press Compress. The tool searches for the highest JPEG quality that still fits under 20 KB, and if the image is too large to fit at any quality it automatically scales the dimensions down until it does. The whole process runs in your browser and takes a second or two.

Will a 20 KB image still be readable?

For a passport-style headshot or a signature, yes — 20 KB is tight but workable because the subject is simple and the dimensions are small. For a detailed landscape or a screenshot full of text, 20 KB will visibly soften the image. If quality matters more than the exact number, try the 50 KB or 100 KB target instead.

Can I compress an image to 50 KB or 100 KB instead?

Yes. The target buttons switch between 20 KB, 50 KB, 100 KB, and 200 KB, and the compressor hits whichever you pick. Larger targets keep noticeably more detail, so use the smallest size the form you're filling in will actually accept rather than the smallest size possible.

Does this work for compressing JPG to 100 KB?

It does. Upload the JPG, select the 100 KB target, and the tool re-encodes it to sit just under that budget. Output is always JPEG, since JPEG is what almost every upload form expects and it compresses photographs far more efficiently than PNG.

Is my photo uploaded to a server?

No. Compression happens entirely inside your browser using the HTML canvas API — the image is never transmitted anywhere, never stored, and never seen by us. You can confirm this by disconnecting from the internet after the page loads: the tool still works.

Why does my PNG come back as a JPG?

Hitting a small KB target reliably requires JPEG, which supports variable quality compression. PNG is lossless and cannot be dialled down to an arbitrary size. If your PNG has a transparent background it is flattened onto white before encoding, because JPEG has no transparency channel.

What if the image still won't reach 20 KB?

The tool progressively reduces the dimensions and retries, so this is rare. If it does happen, the result shown is the smallest it could produce while remaining legible. Cropping tighter — for a headshot, cropping to just the face and shoulders — removes detail the encoder has to spend bytes on and usually gets you under the limit.

Does compressing an image reduce its dimensions?

Only if it has to. The compressor first tries to reach the target by lowering JPEG quality at the original dimensions. Downscaling is a fallback for when quality reduction alone isn't enough, which is common for large phone photos being squeezed to 20 KB.

Compress Image to 20KB

Shrink any JPG, PNG, or WebP to an exact KB target — free, and entirely in your browser.

Compressed inside your browser — your image is never uploaded or stored

Drop your image here, or click to browse

JPG, PNG, WebP, BMP — up to 50 MB

Free 20KB Image Compressor

Resize an image to 20 KB — without uploading it anywhere

Most online compressors send your photo to a server. This one doesn't. The image is decoded and re-encoded by your own browser, which means it works offline once the page has loaded, and your passport photo, signature, or ID scan is never transmitted or stored.

Exact 20 KB targetAlso 50 / 100 / 200 KBJPG, PNG, WebPNever uploaded

How it hits an exact size

JPEG quality and file size aren't linearly related, so you can't simply calculate the right setting. The tool binary-searches the quality scale, encoding the image repeatedly to converge on the sharpest version that still fits your budget.

If even the lowest quality overshoots — common for a 12-megapixel phone photo being pushed to 20 KB — it reduces the dimensions and searches again, repeating until the file fits.

Size Guide

Choosing between 20 KB, 50 KB, 100 KB and 200 KB

Use the smallest target the form actually requires — not the smallest the tool can produce. Every kilobyte you give back to the encoder is detail retained in your photo.

Why 20 KB specifically?

20 KB is a common upload ceiling on government and examination portals, particularly for passport photographs and scanned signatures. Forms that reject your photo for being 'too large' are usually enforcing a limit in this range.

Quality at each size

At 20 KB a small headshot stays recognisable but loses fine texture. At 50 KB most portrait photos look clean. At 100–200 KB the compression becomes hard to spot at normal viewing size.

Nothing leaves your device

Because the encoding runs on the HTML canvas in your own browser, the tool works offline once loaded and your photo is never transmitted, stored, or logged anywhere.

How To Compress an Image to 20KB

Four steps to a 20 KB photo

Step 1

Add your image

Drag a JPG, PNG, WebP, or BMP onto the drop zone, or click to browse. Nothing uploads — the file is read directly by your browser.

Step 2

Pick a size target

Choose 20 KB, 50 KB, 100 KB, or 200 KB depending on what the form you're filling in requires. 20 KB is the default.

Step 3

Compress

The tool binary-searches JPEG quality to find the sharpest version that fits your budget, scaling dimensions down only if it must.

Step 4

Download

Check the preview and the final size, then download the JPG. Not small enough? Crop tighter or choose a different target and run it again.

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FAQ

Frequently asked questions about compressing images to 20KB

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