Compress an image to under 100KB
Get a photo under 100KB in your browser, with the target set for you. The most commonly demanded limit and the most achievable.
KB here means 1,000 bytes, so a file under the number you set is under it whichever convention the form on the other end uses.
Drop JPG, PNG, WebP, HEIC, AVIF, GIF, BMP files here or paste from the clipboard.
Your files are processed on this device. Nothing is uploaded.
Where this limit comes from
One hundred kilobytes is the single most common figure on application forms anywhere in the world. Visa and passport portals, civil service and university examination systems, tax and licensing sites and a long tail of government services all settle on it, usually alongside a dimension requirement and a demand for JPG specifically. It is also a sensible self-imposed budget for images on a page that has to load quickly on a slow connection.
What fits in 100 KB
A full photograph that still looks like one. A hundred thousand bytes generally buys somewhere between 1,000 and 1,400 pixels on the long edge at a quality nobody would question, which is larger than most forms ask for and larger than most screens display an uploaded photo at. Portraits and product shots do better than landscapes, because empty background compresses almost for free while foliage and texture don’t.
Why 100KB is the number everyone picks
It isn’t arbitrary. A hundred kilobytes is roughly where a photograph stops being a burden on a slow connection while still being unambiguously a photograph and it is a round figure in the units the people writing the requirement were thinking in. Once a few large government systems chose it, everything built to interoperate with them chose it too.
The practical consequence is that a lot of people meet this exact requirement every day, usually with a photo taken on a phone at ten times the size.
Doing it in one pass
The two things a form usually demands together are a size and a set of dimensions. Compressing first and resizing afterwards undoes the compression work, because re-encoding a resized image is a fresh compression pass. Resize first or cap the width here and let the tool compress within the cap.
What quality to expect
For a normal phone photo at around 1,200 pixels wide, expect a quality setting in the 55 to 75 range. That is well inside the zone where nobody looking at the image would describe it as compressed, though you would see the difference from the original at full zoom on a large screen.
If it’ll not fit
Crop. Every pixel of background is competing with the subject for the same hundred thousand bytes and a tighter crop is always the cheapest improvement. Failing that, switch to WebP if the destination accepts it.
Common questions
My form wants under 100KB and a specific pixel size. How do I do both?
Set the width cap in the tool to the pixel width the form asks for, then set the target size. The tool applies the cap first and searches quality within it, so both constraints are met in one pass. If the form specifies an exact height too, use the resizer first, then compress the result here.
Why does the tool sometimes shrink the image even when I didn’t ask it to?
Only when quality alone can’t reach the target. It searches quality down to a floor of about 45 and below that it reduces dimensions instead, because a smaller sharp image beats a full-size smeared one. The row tells you the dimensions and quality it settled on so nothing is hidden.
The form insists on JPG. Is that what I get?
Set the format selector to JPG and yes. It defaults to keeping whatever format you dropped in, which for an iPhone photo would be a HEIC that no form will accept, so it falls back to JPG automatically in that case.
Is the photo uploaded anywhere to be compressed?
No. The compression runs in this tab, which matters here more than on most pages, because the photos people compress to 100KB are frequently passport scans, identity documents and application photographs. Nothing is transmitted and there is no server involved.
Guides
Compress to a specific size
Each of these opens the tool with the target already set.