Compress Image to 500KB Online
500KB gives you room to breathe: multi-page scans, product shots, and detailed diagrams stay crisp while still slipping under strict attachment limits. CompressIO targets exactly 500KB automatically — no sliders, no trial and error.
Free · No sign-up · 100% private — works entirely in your browser
Corporate mail gateways and court e-filing systems often enforce a 500KB cap.
Photo-heavy images remain near-original quality at this size.
Drop one image or a whole batch — every result lands at 500KB or below, free.
Frequently asked questions
How accurate is the 500KB target?+
The compressor iterates until the file fits at or just under 500KB, so the result is reliably within the limit — usually within a few KB.
Do you support PNG files?+
Yes. PNG and WebP are accepted and converted to optimized JPEG, which is what makes such small sizes possible for photos.