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Compress an image to 30 KB
To get an image under 30 KB, PixelFit aims at 30,000 bytes or less, so forms counting 1 KB as 1000 or 1024 bytes both accept it. Estimated from our measured encodes, that is about 394 × 295 pixels for a 4:3 photo at quality 75, or 401 × 500 for a portrait.
Under 30 KB
JPG · under 30 KB (at most 30,000 bytes) · original pixel size · white background
PixelFit aims at 30,000 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 30 KB means in bytes
30 KB is 30,720 bytes when 1 KB = 1024 bytes (30 × 1024) and 30,000 bytes when a server counts 1 KB = 1000 bytes. The 720-byte gap matters only near the limit. PixelFit aims at 30,000 bytes or less and prints the exact byte count, so you can compare it with the form.
30 KB is 0.029 MB; 341 such files fit in 10 MB. Uncompressed, the 394 × 295 photo that fits here would need 341 KB of raw pixels, so JPEG at quality 75 packs it about 12 to 1.
Largest pixel size that fits 30 KB
The biggest image of each kind, in its own aspect ratio, that stays at or below 30,000 bytes.
| Image | JPG q60 | JPG q75 | JPG q90 | WebP q75 |
|---|---|---|---|---|
| Head-and-shoulders portrait | 475 × 593 | 401 × 500 | 290 × 362 | 580 × 724 |
| Outdoor landscape (12 MP phone photo) | 457 × 342 | 394 × 295 | 303 × 227 | 421 × 315 |
| Scanned typed document page | 427 × 536 | 370 × 464 | 284 × 356 | 439 × 551 |
| Handwritten letter with signature | 819 × 673 | 676 × 555 | 467 × 383 | 1,060 × 871 |
| Flat-colour graphic (flag) | 1,252 × 876 | 1,068 × 747 | 780 × 546 | 1,773 × 1,241 |
A 12 MP phone photo at 30 KB
Our 12 MP landscape sample (4032 × 3024) is about 4.15 MB at quality 90, 145 times the 30 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 30 KB near 394 × 295 (0.12 MP, 0.95 % of the original pixels). Quality 60 allows 457 × 342; quality 90 needs 303 × 227.
JPEG quality for fixed pixel sizes under 30 KB
When a form fixes the pixels, only quality can move. Highest quality (of 100) that keeps each size at or under 30,000 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 71 (29.1 KB) | quality 85 (28.7 KB) |
| 600 × 600 (2 × 2 inch at 300 DPI) | portrait photo | quality 45 (29 KB) | quality 77 (28.6 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 30 KB
Real encodes from our test set at quality 75: the largest file that stays under 30,000 bytes and the smallest that goes over.
| Image | Largest under 30 KB | Smallest over 30 KB |
|---|---|---|
| Head-and-shoulders portrait | 400 × 500: 29,830 B | 480 × 600: 39,317 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) | 1000 × 700: 27,529 B | 1200 × 840: 34,937 B |
JPG, WebP or PNG at 30 KB
At quality 75, WebP holds 421 × 315 of the landscape photo in 30 KB, JPG 394 × 295: 14 % more pixels. Portrait gain: 109 %. Typed page gain: 41 %. A moderate gain for the landscape photo at 30 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 30 KB it holds a flat graphic of 678 × 474 pixels but a photo of only 139 × 104, against 394 × 295 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 30 KB
2 of the 6 sizes above keep quality 75 or better under 30 KB (300 × 120, 200 × 230); 2 miss even at quality 30 (800 × 600, 1200 × 1600). At 394 × 295, quality 90 costs 64 % more bytes than quality 75.
A typed page reaches 427 × 536 at quality 60 in 30 KB, about 46 DPI if it is an A4 sheet.
How to compress an image to 30 KB
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Open the tool above
It is preset to 30 KB (30,000 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 30 KB.
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Pixel size: only if asked
On auto, a typical photo stops near 394 × 295 at about quality 75.
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Download and check
name-30kb.jpg comes with its byte count, pixels and quality.
Forms that ask for 30 KB
Upload specs in our dataset with exactly 30 KB. Verify with the official notice before you submit.
30 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 30 KB?
Drop it into the tool here, preset to 30 KB. It searches JPEG quality (at most 8 encodes per pixel size), then scales pixels down if needed, until the file is 30,000 bytes or less. A 4:3 photo typically lands near 394 × 295 at about quality 75.
How do I compress an image to less than 30 KB without losing quality?
Give up pixels before quality: at quality 75, 30 KB holds 394 × 295 of a photo and 401 × 500 of a portrait; quality 90 at 394 × 295 costs 64 % more bytes.
Is 30 KB 30,000 or 30,720 bytes?
Both readings exist: 30,720 bytes (1 KB = 1024) or 30,000 bytes (1 KB = 1000). 30,000 bytes or less passes both.
Can I compress a PNG to 30 KB?
Yes, but a full-colour PNG photo stays big: about 139 × 104 pixels in 30 KB, versus 678 × 474 for a flat graphic. As a JPG the photo reaches 394 × 295.
What pixel size fits 30 KB?
At quality 75: a photo 394 × 295, a portrait 401 × 500, a typed page 370 × 464.
Related
Nearby file sizes
- Compress to 25 KB photo ≈ 357 × 267
- Compress to 20 KB photo ≈ 317 × 237
- Compress to 16 KB photo ≈ 282 × 211
- Compress to 35 KB photo ≈ 426 × 319
- Compress to 40 KB photo ≈ 455 × 341
- Compress to 45 KB photo ≈ 483 × 362
More ways to hit 30 KB
- JPG to PDF under 30 KB One image as a PDF
- Between 30 KB and 50 KB Minimum and maximum
- Image resizer with KB target Any size, pixels and format
Pixel sizes that fit 30 KB
- 160×600 banner about 24.5 KB as a quality-75 JPG
- 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