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Compress an image to 800 KB
To get an image under 800 KB, PixelFit aims at 800,000 bytes or less, so forms counting 1 KB as 1000 or 1024 bytes both accept it. Estimated from our measured encodes, that is about 2,054 × 1,540 pixels for a 4:3 photo at quality 75, or 2,868 × 3,582 (extrapolated) for a portrait.
Under 800 KB
JPG · under 800 KB (at most 800,000 bytes) · original pixel size · white background
PixelFit aims at 800,000 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 800 KB means in bytes
800 KB is 819,200 bytes when 1 KB = 1024 bytes (800 × 1024) and 800,000 bytes when a server counts 1 KB = 1000 bytes. The 19,200-byte gap matters only near the limit. PixelFit aims at 800,000 bytes or less and prints the exact byte count, so you can compare it with the form.
800 KB is 0.78 MB; 12 such files fit in 10 MB. Uncompressed, the 2,054 × 1,540 photo that fits here would need 9.05 MB of raw pixels, so JPEG at quality 75 packs it about 12 to 1.
Largest pixel size that fits 800 KB
The biggest image of each kind, in its own aspect ratio, that stays at or below 800,000 bytes.
| Image | JPG q60 | JPG q75 | JPG q90 | WebP q75 |
|---|---|---|---|---|
| Head-and-shoulders portrait | 3,543 × 4,425* | 2,868 × 3,582* | 1,993 × 2,489 | 4,521 × 5,646* |
| Outdoor landscape (12 MP phone photo) | 2,386 × 1,789 | 2,054 × 1,540 | 1,604 × 1,203 | 2,222 × 1,666 |
| Scanned typed document page | 3,299 × 4,145* | 2,675 × 3,361* | 1,834 × 2,304 | 4,560 × 5,730* |
| Handwritten letter with signature | 5,051 × 4,152* | 4,032 × 3,314* | 2,697 × 2,217 | 6,431 × 5,287* |
A 12 MP phone photo at 800 KB
Our 12 MP landscape sample (4032 × 3024) is about 4.15 MB at quality 90, 5 times the 800 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 800 KB near 2,054 × 1,540 (3.2 MP, 26 % of the original pixels). Quality 60 allows 2,386 × 1,789; quality 90 needs 1,604 × 1,203.
JPEG quality for fixed pixel sizes under 800 KB
When a form fixes the pixels, only quality can move. Highest quality (of 100) that keeps each size at or under 800,000 bytes:
| Pixel size | Measured on | JPG | WebP |
|---|---|---|---|
| 1080 × 1080 (square social post) | landscape photo | quality 95+ (640 KB) | quality 95+ (596 KB) |
| 1920 × 1080 (Full HD frame) | landscape photo | quality 88 (774 KB) | quality 90 (762 KB) |
| 1240 × 1754 (A4 page at 150 DPI) | scanned typed page | quality 95+ (643 KB) | quality 95+ (471 KB) |
| 2480 × 3508 (A4 page at 300 DPI) | scanned typed page | quality 75 (761 KB) | quality 88 (749 KB) |
| 3000 × 4000 (12 MP portrait frame) | portrait photo | quality 69 (771 KB) | quality 85 (742 KB) |
| 4032 × 3024 (12 MP phone photo) | landscape photo | no: fewer pixels needed | no: fewer pixels needed |
JPG, WebP or PNG at 800 KB
At quality 75, WebP holds 2,222 × 1,666 of the landscape photo in 800 KB, JPG 2,054 × 1,540: 17 % more pixels. Portrait gain: 148 % (extrapolated). Typed page gain: 191 % (extrapolated). A moderate gain for the landscape photo at 800 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 800 KB it holds a flat graphic of more than 9,561 × 6,692 pixels but a photo of only 730 × 547, against 2,054 × 1,540 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 800 KB
4 of the 6 sizes above keep quality 75 or better under 800 KB (1080 × 1080, 1920 × 1080, 1240 × 1754, 2480 × 3508); 1 misses even at quality 30 (4032 × 3024). At 2,054 × 1,540, quality 90 costs 60 % more bytes than quality 75.
A typed page reaches 3,299 × 4,145 (extrapolated) at quality 60 in 800 KB, about 354 DPI if it is an A4 sheet.
How to compress an image to 800 KB
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Open the tool above
It is preset to 800 KB (800,000 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 800 KB.
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Pixel size: only if asked
On auto, a typical photo stops near 2,054 × 1,540 at about quality 75.
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Download and check
name-800kb.jpg comes with its byte count, pixels and quality.
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 800 KB?
Drop it into the tool here, preset to 800 KB. It searches JPEG quality (at most 8 encodes per pixel size), then scales pixels down if needed, until the file is 800,000 bytes or less. A 4:3 photo typically lands near 2,054 × 1,540 at about quality 75.
How do I compress an image to less than 800 KB without losing quality?
Give up pixels before quality: at quality 75, 800 KB holds 2,054 × 1,540 of a photo and 2,868 × 3,582 (extrapolated) of a portrait; quality 90 at 2,054 × 1,540 costs 60 % more bytes.
Is 800 KB 800,000 or 819,200 bytes?
Both readings exist: 819,200 bytes (1 KB = 1024) or 800,000 bytes (1 KB = 1000). 800,000 bytes or less passes both.
Can I compress a PNG to 800 KB?
Yes, but a full-colour PNG photo stays big: about 730 × 547 pixels in 800 KB, versus more than 9,561 × 6,692 for a flat graphic. As a JPG the photo reaches 2,054 × 1,540.
What pixel size fits 800 KB?
At quality 75: a photo 2,054 × 1,540, a portrait 2,868 × 3,582 (extrapolated), a typed page 2,675 × 3,361 (extrapolated).
Related
Nearby file sizes
- Compress to 700 KB photo ≈ 1,913 × 1,434
- Compress to 600 KB photo ≈ 1,763 × 1,322
- Compress to 512 KB photo ≈ 1,623 × 1,217
- Compress to 900 KB photo ≈ 2,191 × 1,643
- Compress to 1 MB photo ≈ 2,322 × 1,741
- Compress to 1.5 MB photo ≈ 2,918 × 2,188
More ways to hit 800 KB
- JPG to PDF under 800 KB One image as a PDF
- Image resizer with KB target Any size, pixels and format
Pixel sizes that fit 800 KB
- 5×7 inch print about 778 KB as a quality-75 JPG
- 7×5 inch print about 778 KB as a quality-75 JPG
- 2048×1536 (QXGA) about 777 KB as a quality-75 JPG
- 2560×1080 (UWFHD) about 689 KB as a quality-75 JPG