Local target-size compression

Compress Image to 20KB

Prepare a JPG, PNG, or WebP for a 20KB upload limit. Strict mode can lower JPG or WebP quality and reduce dimensions when needed; Keep dimensions never resizes. PicRecast shows the verified output bytes and does not claim success when the target cannot be met.

Runs in your browser
No image upload
Review before download

Choose an image

Add one supported image. A replacement is accepted only after it passes local validation.

Static JPG/JPEG, PNG, and WebP. Animated WebP is rejected. Processing stays in this browser.

Set target and compression behavior

Choose exact decimal KB or MB, whether dimensions may change, and the output format.

Exact file-size target

Target valueUnit

Exact target: 20,000 bytes (1 KB = 1,000 bytes; 1 MB = 1,000,000 bytes).

Compression behavior

Strict target — may reduce dimensionsQuality is tested first. If needed, pixel dimensions are reduced without cropping or stretching.Keep dimensions — find the closest resultOriginal pixel dimensions stay fixed. A result above the target is labeled clearly, not reported as achieved.

Output formatOutput format

JPG transparency backgroundFill transparent pixels with

Review the actual result

PicRecast tests real encoded files and reports the selected file's exact bytes before download.

Choose an image to begin.

Three-step workflow

How to compress an image to 20KB

1Choose a JPG, PNG, or static WebP.
2Review the 20,000-byte target, mode, and output format.
3Run the local search and inspect actual bytes, quality, and final dimensions.

Choose the tradeoff that fits this target

Target bytes, image detail, pixel dimensions, and output format interact. Review the verified result instead of relying on an estimate.

A 20KB limit leaves little room

20KB is a very small limit. Large images often need obvious quality or dimension tradeoffs, so inspect text, edges, and fine detail before using the download.

Choose dimension changes deliberately

Strict can resize proportionally after testing quality. Keep dimensions never resizes and may remain above 20KB.

JPG and WebP usually have more room

JPG or WebP is often easier to fit under a strict upload limit than lossless PNG. Format never changes unless you select it.

When 20KB is unreachable

Container overhead, minimum quality, minimum dimensions, and the 32-candidate budget are real limits; the smallest verified result is shown.

File size is not pixel size

Width and height describe pixels; KB and MB describe encoded bytes. Reducing either quality or dimensions can change file size.

JPG, PNG, and WebP differ

JPG and WebP support quality search. PNG uses lossless OxiPNG, so a very small target may require proportional resizing.

Metadata may be removed

Newly encoded files may not retain EXIF metadata or color profiles. Keep the original and inspect the download.

Why a result can miss the target

Format overhead, safe quality limits, minimum dimensions, and bounded attempts can leave a verified result above the target.

Local processing boundary

Validation, candidate encoding, comparison, preview, and download stay in this browser. Images are not sent to a processing API.

20KB compression FAQ

Will the compressed image be 20KB or less?

In Strict mode, PicRecast reports success only when the output is at or below 20,000 bytes. If the target cannot be reached within the supported compression and dimension limits, the smallest verified result is shown instead. Keep dimensions can also remain above target because it never resizes.

Why did dimensions change?

Strict mode reduced dimensions only after minimum quality at the original dimensions could not meet 20KB.

Is PNG converted to JPG automatically?

No. PNG stays PNG unless you explicitly select another format.

Are candidate images uploaded?

No. Candidate encoding and selection are browser-local.