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Compress an image to 25 KB
To get an image under 25 KB, PixelFit aims at 25,000 bytes or less, so forms counting 1 KB as 1000 or 1024 bytes both accept it. Estimated from our measured encodes, that is about 357 × 267 pixels for a 4:3 photo at quality 75, or 354 × 442 for a portrait.
Under 25 KB
JPG · under 25 KB (at most 25,000 bytes) · original pixel size · white background
PixelFit aims at 25,000 bytes or less, so the file passes whether the form counts 1 KB as 1,000 or 1,024 bytes.
Fit, background and padding white background
Saving presets is part of Pro.
The result appears here: the exact byte count, pixel size and quality, the size before and after, a preview and a download button.
The batch kit (one ZIP for up to 500 photos, several photos merged into one PDF) is part of Pro.
What 25 KB means in bytes
25 KB is 25,600 bytes when 1 KB = 1024 bytes (25 × 1024) and 25,000 bytes when a server counts 1 KB = 1000 bytes. The 600-byte gap matters only near the limit. PixelFit aims at 25,000 bytes or less and prints the exact byte count, so you can compare it with the form.
25 KB is 0.024 MB; 409 such files fit in 10 MB. Uncompressed, the 357 × 267 photo that fits here would need 279 KB of raw pixels, so JPEG at quality 75 packs it about 11 to 1.
Largest pixel size that fits 25 KB
The biggest image of each kind, in its own aspect ratio, that stays at or below 25,000 bytes.
| Image | JPG q60 | JPG q75 | JPG q90 | WebP q75 |
|---|---|---|---|---|
| Head-and-shoulders portrait | 420 × 524 | 354 × 442 | 257 × 320 | 503 × 628 |
| Outdoor landscape (12 MP phone photo) | 417 × 312 | 357 × 267 | 275 × 206 | 383 × 287 |
| Scanned typed document page | 389 × 488 | 336 × 422 | 258 × 324 | 396 × 497 |
| Handwritten letter with signature | 734 × 603 | 607 × 499 | 420 × 345 | 945 × 776 |
| Flat-colour graphic (flag) | 1,091 × 763 | 924 × 646 | 670 × 469 | 1,509 × 1,056 |
A 12 MP phone photo at 25 KB
Our 12 MP landscape sample (4032 × 3024) is about 4.15 MB at quality 90, 174 times the 25 KB budget; even quality 30 leaves 1.26 MB (extrapolated from encodes up to 3,000 px). So the pixels must go down too.
At about quality 75 it fits 25 KB near 357 × 267 (0.1 MP, 0.78 % of the original pixels). Quality 60 allows 417 × 312; quality 90 needs 275 × 206.
JPEG quality for fixed pixel sizes under 25 KB
When a form fixes the pixels, only quality can move. Highest quality (of 100) that keeps each size at or under 25,000 bytes:
| Pixel size | Measured on | JPG | WebP |
|---|---|---|---|
| 300 × 120 (signature strip) | handwritten page | quality 95+ (10.1 KB) | quality 95+ (6.8 KB) |
| 200 × 230 (small ID photo) | portrait photo | quality 95+ (21.9 KB) | quality 95+ (17.4 KB) |
| 413 × 531 (35 × 45 mm at 300 DPI) | portrait photo | quality 60 (24.4 KB) | quality 80 (23.5 KB) |
| 600 × 600 (2 × 2 inch at 300 DPI) | portrait photo | quality 33 (24.1 KB) | quality 68 (24.3 KB) |
| 800 × 600 (4:3 web photo) | landscape photo | no: fewer pixels needed | no: fewer pixels needed |
| 1200 × 1600 (3:4 portrait upload) | portrait photo | no: fewer pixels needed | no: fewer pixels needed |
Measured JPEG files either side of 25 KB
Real encodes from our test set at quality 75: the largest file that stays under 25,000 bytes and the smallest that goes over.
| Image | Largest under 25 KB | Smallest over 25 KB |
|---|---|---|
| Head-and-shoulders portrait | 320 × 400: 21,568 B | 400 × 500: 29,830 B |
| Outdoor landscape (12 MP phone photo) | 300 × 225: 18,059 B | 400 × 300: 30,893 B |
| Scanned typed document page | 318 × 400: 22,368 B | 398 × 500: 34,663 B |
| Handwritten letter with signature | 600 × 493: 24,480 B | 800 × 658: 39,979 B |
| Flat-colour graphic (flag) | 800 × 560: 20,958 B | 1000 × 700: 27,529 B |
JPG, WebP or PNG at 25 KB
At quality 75, WebP holds 383 × 287 of the landscape photo in 25 KB, JPG 357 × 267: 15 % more pixels. Portrait gain: 102 %. Typed page gain: 39 %. A moderate gain for the landscape photo at 25 KB, a large one for portraits: where WebP is accepted, use it for those. Many portals accept only JPG/JPEG, so this page starts in JPG.
A full-colour PNG is lossless, so its size follows the content. In 25 KB it holds a flat graphic of 581 × 406 pixels but a photo of only 126 × 94, against 357 × 267 as a quality-75 JPG. Reducing a PNG to a palette of up to 256 colours (PixelFit does this when a PNG must shrink) helps graphics far more than photos.
Which uploads fit comfortably in 25 KB
2 of the 6 sizes above keep quality 75 or better under 25 KB (300 × 120, 200 × 230); 2 miss even at quality 30 (800 × 600, 1200 × 1600). At 357 × 267, quality 90 costs 63 % more bytes than quality 75.
A typed page reaches 389 × 488 at quality 60 in 25 KB, about 42 DPI if it is an A4 sheet.
How to compress an image to 25 KB
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Open the tool above
It is preset to 25 KB (25,000 bytes or less), JPG output.
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Add your image
Drop, paste or pick it; a PNG, WebP or (where the browser opens it) HEIC file becomes a JPG under 25 KB.
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Pixel size: only if asked
On auto, a typical photo stops near 357 × 267 at about quality 75.
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Download and check
name-25kb.jpg comes with its byte count, pixels and quality.
Forms that ask for 25 KB
Upload specs in our dataset with exactly 25 KB. Verify with the official notice before you submit.
25 KB limits
Sources
- Measured by PixelFit with sharp 0.35.5 / libvips 8.18.7 on 31 October 2026.
- Sample images, Wikimedia Commons, checked 31 October 2026: landscape (CC0 1.0) commons.wikimedia.org/w/index.php?curid=154070378; portrait commons.wikimedia.org/w/index.php?curid=23956389; typed page commons.wikimedia.org/w/index.php?curid=194775753; handwritten letter commons.wikimedia.org/w/index.php?curid=90423615; flag commons.wikimedia.org/w/index.php?curid=361734 (public domain).
- Binary prefixes, NIST, checked 31 October 2026: physics.nist.gov/cuu/Units/binary.html
Frequently asked questions
How do I compress an image to 25 KB?
Drop it into the tool here, preset to 25 KB. It searches JPEG quality (at most 8 encodes per pixel size), then scales pixels down if needed, until the file is 25,000 bytes or less. A 4:3 photo typically lands near 357 × 267 at about quality 75.
How do I compress an image to less than 25 KB without losing quality?
Give up pixels before quality: at quality 75, 25 KB holds 357 × 267 of a photo and 354 × 442 of a portrait; quality 90 at 357 × 267 costs 63 % more bytes.
Is 25 KB 25,000 or 25,600 bytes?
Both readings exist: 25,600 bytes (1 KB = 1024) or 25,000 bytes (1 KB = 1000). 25,000 bytes or less passes both.
Can I compress a PNG to 25 KB?
Yes, but a full-colour PNG photo stays big: about 126 × 94 pixels in 25 KB, versus 581 × 406 for a flat graphic. As a JPG the photo reaches 357 × 267.
What pixel size fits 25 KB?
At quality 75: a photo 357 × 267, a portrait 354 × 442, a typed page 336 × 422.
Related
Nearby file sizes
- Compress to 20 KB photo ≈ 317 × 237
- Compress to 16 KB photo ≈ 282 × 211
- Compress to 15 KB photo ≈ 273 × 204
- Compress to 30 KB photo ≈ 394 × 295
- Compress to 35 KB photo ≈ 426 × 319
- Compress to 40 KB photo ≈ 455 × 341
More ways to hit 25 KB
- Between 10 KB and 25 KB Minimum and maximum
- Image resizer with KB target Any size, pixels and format
Pixel sizes that fit 25 KB
- 336×280 banner about 24 KB as a quality-75 JPG
- 300×300 square about 23.1 KB as a quality-75 JPG
- 970×90 banner about 22.4 KB as a quality-75 JPG
- 320×240 (QVGA) about 19.9 KB as a quality-75 JPG