Compress a photo to 100 KB
100 KB is a common limit for ID photos, profile pictures and document photos on online forms. FitsUnder keeps the full resolution whenever it can and finds the best JPG quality that still fits under 100 KB.
The file will be made smaller than this size.
If the form also asks for exact dimensions in pixels, resize first, then compress to 100 KB.
Other limits
What happens to your file
It stays on your device
FitsUnder runs inside your browser. The file is read, compressed and saved on your own computer or phone — it is never sent anywhere. That makes it safe for passports, contracts and medical records.
Quality comes first
Other compressors make you guess between “low”, “medium” and “high”. FitsUnder starts from the best quality and steps down only as far as your limit requires. Resolution is reduced only when that alone isn’t enough.
PDF text stays text
In a PDF, only the pictures are re-compressed. Text, fonts and links stay as they were, so the document can still be searched and copied. Pages become images only as a last resort, and you’ll see it in the result.
Questions
Is 2 MB 2,000,000 bytes or 2,097,152 bytes?
Websites use both. FitsUnder always aims for the smaller number — 2,000,000 bytes for 2 MB, 200,000 bytes for 200 KB — so the file passes whichever one the form checks.
Will my file look worse?
Only as much as the limit forces. FitsUnder starts from the highest quality and steps down until the file fits, and reduces resolution only when lower quality alone would look bad. Compare before and after in the preview before you download.
Why did my PNG or HEIC photo come back as a JPG?
JPG stores photos many times smaller and every upload form accepts it. Pictures with transparent areas, such as logos, stay PNG.
Is it safe for passports and contracts?
Yes. Your file is read and compressed by your own browser and saved straight back to your device. It is never sent to a server, so nobody else can see it.
Is it free?
Yes. No sign-up, no watermark, no daily limit.