Compress Image to 800KB
Reduce JPG, PNG or WebP image size to 800KB or less with a real target-size workflow. Review the result before using it for an upload or form.
Smart target workflow
Compress to 800KB without guesswork
Batch up to 50 images, review the real output, then download images, ZIP or a combined PDF.
Compressing an image to 800 KB: what actually happens
On this page 800 KB means at most 800,000 bytes. That also passes a portal that counts 1 KB as 1,024 bytes (a limit of 819,200 bytes), so you do not have to know which definition the form uses.
Our 12-megapixel photo-style test image fitted under 800 KB at its full 4032 × 3024 pixels as a JPG (773.2 KB), so at this target the tool only lowers JPEG quality. That is 0.52 bits per pixel; at the 10 MB target the same image kept 2.58 bits per pixel, so zoom in on fine detail before you upload. Real camera photos with more texture than our test image need more bytes for the same pixel size.
Where a 800 KB limit comes from, and whether this page meets it
US visa photo
The State Department limits visa photos to 240 kB. At 800 KB the file is more than three times over that limit; visa photos need the 200 KB page. A 800 KB file is larger than that limit, so use a smaller target page for this portal.
UK passport digital photo
GOV.UK accepts digital photos between 50 KB and 10 MB. 800 KB is accepted, and at this target our 12 MP test image kept its full size. A 800 KB file from this page is inside that range.
800 KB in numbers
Worked out from the byte limit, and from what this page produced with our test files.
| Measure | Value |
|---|---|
| Byte limit used by this page | 800,000 |
| Same limit if a site counts 1 KB = 1,024 bytes | 819,200 |
| Compression needed for a 12 MP photo kept at full size | about 46:1 (36.3 MB of raw pixels into 800 KB) |
| Largest uncompressed square that fits | 516 × 516 pixels |
| Our photo-style test image (4032 × 3024), JPG | 4032 × 3024, 773.2 KB |
| Our scan-style A4 test page, JPG: pixels per inch of paper | about 300 pixels per inch (2480 pixels across 8.27 inches) |
Sources: U.S. Department of State, "Digital image requirements (visa photos)" (https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/photos/digital-image-requirements.html); GOV.UK, "Photos for passports" (https://www.gov.uk/photos-for-passports). Checked 2026-10-19. Portal rules change between recruitment cycles and releases; the notice or help page for your own upload has the final say.
How to get an image under 800 KB
Add the original
Use the largest, cleanest copy you have. Compressing a file that was already squeezed by a chat app loses detail twice.
Keep the strategy on Auto
Auto lowers the quality first and reduces the pixel size only when quality alone cannot reach 800 KB. "Quality first" never reduces the dimensions and stops with a message instead; "Size first" shrinks the image sooner and keeps more quality per pixel.
Choose JPG or WebP
JPG is accepted by every form. WebP can keep more pixels in the same budget, but only use it when the site lists WebP as allowed.
Check the result
The results panel shows the final pixel size and KB. Zoom in on faces and small text before uploading.
What this page produced from our test files
We ran three fixed test files through this page in headless Chrome 129.0.6668.29 on 2026-10-19, with the default Auto strategy. Sizes are the bytes of the downloaded files. The test files are generated from a fixed seed so anyone can repeat the run; they are not customer photos.
| Test file | Format | Output pixels | File size |
|---|---|---|---|
| Photo-style test image, 4032 × 3024 JPG (2.57 MB) | JPG | 4032 × 3024 | 773.2 KB |
| Photo-style test image, 4032 × 3024 JPG (2.57 MB) | WEBP | 4032 × 3024 | 763 KB |
| Screenshot-style test image, 1920 × 1080 PNG (24.3 KB) | JPG | 1920 × 1080 | 64.1 KB |
| Screenshot-style test image, 1920 × 1080 PNG (24.3 KB) | WEBP | 1920 × 1080 | 7.7 KB |
| Scan-style A4 test page, 2480 × 3508 JPG (3.4 MB) | JPG | 2480 × 3508 | 774.6 KB |
| Scan-style A4 test page, 2480 × 3508 JPG (3.4 MB) | WEBP | 2034 × 2877 | 780.4 KB |
Before you upload a 800 KB file
- If an 800 KB limit is for a document page rather than a photo, a scan keeps text sharper as a smaller crop of the important area than as a whole page squeezed to 800 KB.
- Of the targets we measured, 800 KB was the smallest at which a full A4 page scanned at 300 dots per inch (2480 × 3508 pixels) came back as JPG with no pixels removed, at 793 KB. The same scan as WebP was cut to 2034 × 2877.
- Our scan-style A4 test page stayed at 2480 pixels across (about 300 pixels per inch of paper), enough to keep normal body text readable.
- The 1920 × 1080 screenshot-style test image fitted at full size as JPG, because flat colours and sharp edges compress far better than photos.
Frequently asked questions
Does 800 KB mean 1,000 or 1,024 bytes per KB?
Sites use both. This page stays at or below 800,000 bytes, which is under both readings, so the file passes either way.
How large can a photo be at 800 KB?
In our test a 12 MP photo-style image came out at 4032 × 3024 pixels as JPG and 4032 × 3024 as WebP. Busy, noisy photos need more bytes per pixel than plain ones, so your result can be larger or smaller.
Is 800 KB the same as 0.8 MB?
In decimal units, yes: both are 800,000 bytes. A site that counts in binary allows 819,200 bytes for 800 KB but 838,860 bytes for 0.8 MB, so the two limits differ by 19,660 bytes there. This page stays under 800,000 bytes, which passes every reading.
Next steps for your 800 KB file
Related image tools
Check the destination requirement
Upload rules change between services. MAXScanner prepares the file you request, but the receiving form or service is authoritative for its current pixel, format and byte limits.