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Compress an image to 600 KB
To get an image under 600 KB, PixelFit aims at 600,000 bytes or less, so forms counting 1 KB as 1000 or 1024 bytes both accept it. Estimated from our measured encodes, that is about 1,763 × 1,322 pixels for a 4:3 photo at quality 75, or 2,463 × 3,076 (extrapolated) for a portrait.
Under 600 KB
JPG · under 600 KB (at most 600,000 bytes) · original pixel size · white background
PixelFit aims at 600,000 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 600 KB means in bytes
600 KB is 614,400 bytes when 1 KB = 1024 bytes (600 × 1024) and 600,000 bytes when a server counts 1 KB = 1000 bytes. The 14,400-byte gap matters only near the limit. PixelFit aims at 600,000 bytes or less and prints the exact byte count, so you can compare it with the form.
600 KB is 0.59 MB; 17 such files fit in 10 MB. Uncompressed, the 1,763 × 1,322 photo that fits here would need 6.67 MB of raw pixels, so JPEG at quality 75 packs it about 12 to 1.
Largest pixel size that fits 600 KB
The biggest image of each kind, in its own aspect ratio, that stays at or below 600,000 bytes.
| Image | JPG q60 | JPG q75 | JPG q90 | WebP q75 |
|---|---|---|---|---|
| Head-and-shoulders portrait | 3,025 × 3,778* | 2,463 × 3,076* | 1,718 × 2,145 | 3,848 × 4,806* |
| Outdoor landscape (12 MP phone photo) | 2,039 × 1,529 | 1,763 × 1,322 | 1,382 × 1,036 | 1,898 × 1,423 |
| Scanned typed document page | 2,751 × 3,457* | 2,237 × 2,811 | 1,545 × 1,941 | 3,692 × 4,639* |
| Handwritten letter with signature | 4,337 × 3,565* | 3,465 × 2,848* | 2,318 × 1,905 | 5,525 × 4,542* |
| Flat-colour graphic (flag) | over 9,561 × 6,692 | over 9,561 × 6,692 | 8,639 × 6,047* | over 9,561 × 6,692 |
A 12 MP phone photo at 600 KB
Our 12 MP landscape sample (4032 × 3024) is about 4.15 MB at quality 90, 7 times the 600 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 600 KB near 1,763 × 1,322 (2.3 MP, 19 % of the original pixels). Quality 60 allows 2,039 × 1,529; quality 90 needs 1,382 × 1,036.
JPEG quality for fixed pixel sizes under 600 KB
When a form fixes the pixels, only quality can move. Highest quality (of 100) that keeps each size at or under 600,000 bytes:
| Pixel size | Measured on | JPG | WebP |
|---|---|---|---|
| 1080 × 1080 (square social post) | landscape photo | quality 93 (570 KB) | quality 94 (561 KB) |
| 1200 × 1600 (3:4 portrait upload) | portrait photo | quality 95+ (486 KB) | quality 95+ (393 KB) |
| 1920 × 1080 (Full HD frame) | landscape photo | quality 79 (580 KB) | quality 82 (567 KB) |
| 1240 × 1754 (A4 page at 150 DPI) | scanned typed page | quality 93 (556 KB) | quality 95+ (471 KB) |
| 2480 × 3508 (A4 page at 300 DPI) | scanned typed page | quality 63 (583 KB) | quality 85 (583 KB) |
| 3000 × 4000 (12 MP portrait frame) | portrait photo | quality 57 (577 KB) | quality 81 (576 KB) |
Measured JPEG files either side of 600 KB
Real encodes from our test set at quality 75: the largest file that stays under 600,000 bytes and the smallest that goes over.
| Image | Largest under 600 KB | Smallest over 600 KB |
|---|---|---|
| Head-and-shoulders portrait | 2402 × 3000: 571,851 B | none: every measured size fits |
| Outdoor landscape (12 MP phone photo) | 1600 × 1200: 498,311 B | 2000 × 1500: 762,196 B |
| Scanned typed document page | 1910 × 2400: 465,268 B | 2387 × 3000: 666,088 B |
| Handwritten letter with signature | 3000 × 2466: 455,963 B | none: every measured size fits |
| Flat-colour graphic (flag) | 3000 × 2100: 115,604 B | none: every measured size fits |
JPG, WebP or PNG at 600 KB
At quality 75, WebP holds 1,898 × 1,423 of the landscape photo in 600 KB, JPG 1,763 × 1,322: 16 % more pixels. Portrait gain: 144 % (extrapolated). Typed page gain: 172 % (extrapolated). A moderate gain for the landscape photo at 600 KB, a large one for portraits and typed pages: 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 600 KB it holds a flat graphic of 9,458 × 6,620 (extrapolated) pixels but a photo of only 633 × 474, against 1,763 × 1,322 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 600 KB
4 of the 6 sizes above keep quality 75 or better under 600 KB (1080 × 1080, 1200 × 1600, 1920 × 1080, 1240 × 1754). At 1,763 × 1,322, quality 90 costs 60 % more bytes than quality 75.
A typed page reaches 2,751 × 3,457 (extrapolated) at quality 60 in 600 KB, about 296 DPI if it is an A4 sheet.
How to compress an image to 600 KB
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Open the tool above
It is preset to 600 KB (600,000 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 600 KB.
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Pixel size: only if asked
On auto, a typical photo stops near 1,763 × 1,322 at about quality 75.
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Download and check
name-600kb.jpg comes with its byte count, pixels and quality.
Forms that ask for 600 KB
Upload specs in our dataset with exactly 600 KB. Verify with the official notice before you submit.
600 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 600 KB?
Drop it into the tool here, preset to 600 KB. It searches JPEG quality (at most 8 encodes per pixel size), then scales pixels down if needed, until the file is 600,000 bytes or less. A 4:3 photo typically lands near 1,763 × 1,322 at about quality 75.
How do I compress an image to less than 600 KB without losing quality?
Give up pixels before quality: at quality 75, 600 KB holds 1,763 × 1,322 of a photo and 2,463 × 3,076 (extrapolated) of a portrait; quality 90 at 1,763 × 1,322 costs 60 % more bytes.
Is 600 KB 600,000 or 614,400 bytes?
Both readings exist: 614,400 bytes (1 KB = 1024) or 600,000 bytes (1 KB = 1000). 600,000 bytes or less passes both.
Can I compress a PNG to 600 KB?
Yes, but a full-colour PNG photo stays big: about 633 × 474 pixels in 600 KB, versus 9,458 × 6,620 (extrapolated) for a flat graphic. As a JPG the photo reaches 1,763 × 1,322.
What pixel size fits 600 KB?
At quality 75: a photo 1,763 × 1,322, a portrait 2,463 × 3,076 (extrapolated), a typed page 2,237 × 2,811.
Related
Nearby file sizes
- Compress to 512 KB photo ≈ 1,623 × 1,217
- Compress to 500 KB photo ≈ 1,603 × 1,202
- Compress to 400 KB photo ≈ 1,429 × 1,071
- Compress to 700 KB photo ≈ 1,913 × 1,434
- Compress to 800 KB photo ≈ 2,054 × 1,540
- Compress to 900 KB photo ≈ 2,191 × 1,643
More ways to hit 600 KB
- JPG to PDF under 600 KB One image as a PDF
- Image resizer with KB target Any size, pixels and format
Pixel sizes that fit 600 KB
- 1920×1200 (WUXGA) about 579 KB as a quality-75 JPG
- 1500×1500 square about 566 KB as a quality-75 JPG
- 2048×1080 (DCI 2K) about 557 KB as a quality-75 JPG
- A4 at 150 DPI about 548 KB as a quality-75 JPG