Compress Image to 300KB Online

Older guidance for Passport Seva and an earlier JEE Main application cycle both cited a 300KB photograph ceiling. If your current notification states a lower number like 200KB or 250KB, follow that instead — portals update these limits between cycles.

Yes. Many recruitment portals, including NTA's JEE Main brochure, specify certificate and category-document uploads (Class 10 marksheet, disability certificate) in the 50–300KB range, so 300KB comfortably covers that requirement.

Certificate scans often use higher scanner DPI settings (300+ DPI) meant for printing, which produces far more pixel data than a screen or portal actually needs. Re-scan at 150–200 DPI, or use our tool afterward to compress the resulting JPEG down to 300KB.

Check your specific portal's instructions — many now prefer PDF for text documents (better OCR and readability) and reserve JPEG for photographs and signatures specifically. When JPEG is required or accepted for a certificate, our 300KB tool works well.

1KB equals 1,024 bytes in this tool (and in Windows/macOS), so a file listed as under 300KB is at most 307,200 bytes. If a portal's own size checker uses 1,000 bytes per KB instead, your file will still pass since it's comfortably under either definition.

For most photos, yes — at 300KB you can expect a result that looks very high, with only the most detail-obsessed users noticing any difference from the source. The exact outcome still depends on how detailed and high-resolution your original photo is; a simple, well-lit photo compresses more cleanly than a busy, low-light one.

If your form specifies exact dimensions, match those first — commonly your original dimensions. Our tool not needed unless the source file is extremely high-resolution while compressing, so starting with roughly the right dimensions gives the cleanest result.

Yes. Upload your PNG here, select JPG from the Output Format dropdown, and set your target to 300KB — the tool converts and compresses in the same step, which is handy for a scanned certificate.

No, and we structurally can't — there's no upload step in this 300KB tool at all. Everything happens client-side via JavaScript and Canvas, so your file never leaves your device.

Yes, one at a time, which lets the tool fully optimize each file for exactly 300KB rather than applying one generic setting across a batch. You can reset and compress another image immediately after downloading.

Your iPhone is likely saving photos as HEIC, which isn't accepted here (we support JPG, PNG, WebP, AVIF, GIF, and BMP for the 300KB target). Switching to Settings → Camera → Formats → "Most Compatible" saves future photos as JPG, which will upload fine.