Compress an image to 100 KB.
Drop your photos and download each one as a JPG under 100 KB. The quality is lowered first and the pixel dimensions only when that is not enough; the photo is never cropped. It runs in your browser; nothing is uploaded.
Under 100 KB per image, saved as JPG
Limits come from each platform's own help pages, summarised in the guides (checked 24 September 2026).
Who asks for 100 KB.
Lines from Herofab's platform guides that name 100 KB, as a limit, a recommendation or one end of a range. Each row links to the guide and its official source.
| Platform | Rule | What the guide says | Read |
|---|---|---|---|
| TikTok ads | File size | A file size of 100 KB or less is suggested for each image | 12 October 2026 |
| OpenCart | File size | 100–500 KB per image is recommended; the performance guideline is to keep each image under 500 KB and to compress images before upload | 12 October 2026 |
| Omnisend | Total email size | Keep the total email size under 100 KB; Gmail clips larger emails | 12 October 2026 |
100 KB in numbers.
Counted as the compressor counts: 1 KB is 1,000 bytes and 1 MB is 1,000,000 bytes. Bits per pixel divides the limit in bits by the pixels of a 12-megapixel phone photo (4,032 × 3,024 px) kept at full size; the uncompressed size counts 3 bytes per pixel.
- Bytes
- 100,000
- Bits
- 800,000
- Pixels in a 12-megapixel phone photo
- 4,032 × 3,024 = 12,192,768
- Bits per pixel at full size
- 800,000 ÷ 12,192,768 = 0.0656
- Uncompressed, 3 bytes per pixel
- 36,578,304 bytes, 366 times the limit
Other limits.
100 KB, answered.
Which platforms ask for 100 KB?
TikTok ads, OpenCart, and Omnisend. The table on this page gives each rule in full and links to the platform's guide.
How many bytes is 100 KB?
100,000 bytes: the compressor counts 1 KB as 1,000 bytes, the stricter of the two common readings. Counted in units of 1,024, 100 KB would be 102,400 bytes, so a file under 100,000 bytes is under the limit on either count.
How many bits per pixel does 100 KB leave for a 12-megapixel photo?
0.0656, if the photo keeps all 12,192,768 pixels (4,032 × 3,024): 800,000 bits divided by 12,192,768. Uncompressed, at 3 bytes per pixel, the photo is 36,578,304 bytes, 366 times the limit. The compressor lowers the JPG quality first and reduces the pixel dimensions only when that is not enough.
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