Buy Me A Coffee Icon Buy me a coffee
Compress image to KB — shrink a 5 MB photo to an exact target size like 100 KB in your browser

Compress Image to KB — Hit an Exact File Size

Type the size your form or website allows and get a file at or under it. Quality is lowered only as far as needed; if that is not enough, the photo is scaled down. Free, no signup, nothing uploaded.

Target size

Presets

Every file is checked in bytes and only offered for download if it is at or under your limit.

🗜️

Drag & drop JPG / PNG / WebP / HEIC / AVIF images here (up to 20)

or

No images selected

Images
0 / 20
Target
—
Total size
—

    Privacy: decoding (including iPhone HEIC), compression, and ZIP creation run entirely in your browser. Images are not uploaded to our servers, and EXIF/GPS metadata is not copied into the compressed files.

    Compress an Image to a Specific Size in KB

    Upload boxes reject files by size, not by quality. A regular compressor makes you guess a quality percentage, check the result, and try again. This tool works backward from the limit: enter 100 KB, 50 KB, 1 MB, or any number, and every image comes out at or under it, with as much quality and resolution as that size allows.

    Common sizes have their own presets and guides: compress image to 100KB for job, school, and government forms, and compress image to 50KB for strict exam and ID-photo portals and signature scans.

    How the exact-size compression works

    1. Decode on your device. JPG, PNG, WebP, and AVIF use your browser’s decoder; iPhone HEIC/HEIF is decoded with the same in-browser decoder as our HEIC to JPG tool.
    2. Try high quality first. If the file already fits at 92% quality, you get that.
    3. Search the quality. Otherwise a binary search finds the highest quality (down to 55%) whose file is at or under your limit.
    4. Shrink pixels only if needed. If even 55% is too big, the image is scaled down and the search runs again, so you get a smaller but clean picture instead of a blocky full-size one.
    5. Check the bytes. The final file size is compared to the limit in bytes before the Download button appears.

    Is 1 KB 1000 or 1024 bytes?

    It depends on who is counting. Most websites and upload forms use 1 KB = 1000 bytes, so 100 KB means 100,000 bytes. Windows File Explorer and some older systems count 1024 bytes (a KiB), so 100 KB means 102,400 bytes. The tool defaults to 1000 because it is the stricter limit: a file under 100,000 bytes passes either way. Switch to 1024 only if you know the form counts that way and you want the extra 2.4%.

    Which format should I save as?

    FormatBest forWhat to know
    JPGPhotos, forms, portalsAccepted almost everywhere; the default. Transparent areas become white.
    WebPWebsites, CMS uploadsUsually smaller than JPG at the same quality, but some forms only accept JPG/JPEG.
    PNGWhen a form demands PNGLossless, so there is no quality to lower: the tool can only reduce pixel dimensions. Tight targets give small images.
    AutoMixed batchesJPG for normal photos, WebP when the image has transparency.

    Tips for the sharpest result at a small size

    • ✅ Crop first. Pixels you crop away are bytes you can spend on what matters — use the Image Resizer to crop or set exact dimensions, then come back.
    • ✅ Start from the original, not a screenshot or a copy that has already been compressed.
    • ✅ Plain backgrounds compress better than foliage, crowds, or noisy low-light shots.
    • ✅ Want a quality slider instead of a size? The Image Compressor has Max/Balanced/Web presets and optional resize.
    • ✅ Need print size or 300 DPI as well? Set it afterward with the DPI Converter.

    Frequently Asked Questions (FAQ)

    Q: How do I compress an image to a specific size in KB?

    A: Pick a preset (20, 50, 100, 200, 500 KB or 1 MB) or type your own number, choose KB or MB, drop up to 20 images, and click Compress to target. Each file is saved at the highest quality that fits, then you can download it or get all of them as a ZIP.

    Q: Will the compressed file always be under my target size?

    A: Yes. The tool compares the finished file to your limit in bytes and only offers a download when it is at or under it. If an image cannot fit even when shrunk to 16 pixels on a side, you get an error message instead of an oversized file.

    Q: Should I choose 1000 or 1024 bytes per KB?

    A: Leave it on 1000 unless you are sure. Most upload forms count 1 KB as 1000 bytes, and a file under that stricter limit also passes a form that counts 1024. Choose 1024 only when the form or your operating system clearly uses KiB.

    Q: Why did my image get smaller in pixels?

    A: Because quality alone could not reach the size. The tool lowers quality to no less than 55%, and if the file is still too big it reduces the width and height and tries again. A smaller, clean image is usually more usable than a full-size one covered in compression blocks.

    Q: Can I compress iPhone HEIC photos to a KB size?

    A: Yes. Drop .heic or .heif files straight in; they are decoded in your browser and saved as JPG (or WebP/PNG if you choose). Large iPhone photos can take a few seconds each to decode.

    Q: Are my images uploaded to a server?

    A: No. Decoding, compression, and ZIP creation all run in your browser with HTML canvas. Your photos are not uploaded to QuickImgTools servers.

    Q: Does compressing remove EXIF and location data?

    A: Yes. Every output file is re-encoded from the pixels, so camera EXIF, GPS location, and other metadata from the original are not copied into it. To remove metadata without compressing, use the EXIF Remover.

    Q: How many images can I compress at once?

    A: Up to 20 per batch, all to the same target and format. Download them one by one or click Download all (ZIP).