Exact-KB Image Compressor

Presets guess. This tool listens.

"Compress to High quality" is a guess about a file it has never seen. But forms don't speak in High/Medium/Low — they speak in numbers: photo between 20 and 50 KB, signature under 20 KB, attachment under 200 KB. This compressor takes the number as its input. Type "50", and it will find the encoding that lands at or under 50 KB — as close to the line as quality allows, without going over.

How the binary search works (in plain words)

Imagine quality settings from 35% to 95%. The tool encodes at 65%, sees the size, then checks 80% or 50% depending on whether it was too small or too big — halving the search range each time. Within a handful of passes it has found the highest quality that still fits your target. If even 35% quality overshoots (very heavy images), it scales the pixels down slightly and searches again. The result: the best possible quality inside your band.

Which format should you pick?

• JPG — the default for photos and nearly every Indian portal's accepted format.
• PNG — lossless; useful for screenshots with sharp text. Size control comes only from scaling, so hitting small targets may reduce dimensions.
• WebP — modern and efficient, but check your portal accepts it before choosing; many still want JPG only.

One file at a time is deliberate: form uploads are single files, and seeing each before/after pair individually is how you confirm the exact number you will be judged on. Photos taken outdoors compress far better than screenshots full of sharp text — that's why the same target KB looks perfect on one file and forces a small downscale on another. Both results are shown honestly, including when the tool had to settle for "closest possible" instead of an exact hit.

Target the middle of the band

If a portal says "20–50 KB", type 35, not 49.9. File managers round KB differently than portals count bytes, and a file sitting exactly on the ceiling can fail a stricter check. The middle of the band is safe from both sides — this one habit removes an entire category of upload errors.

What number should I actually type?

• Photo bands — "20–50 KB": type 35. "Under 50 KB": type 45.
• Signature bands — "10–20 KB": type 15.
• Document attachments — "max 200 KB": type 180 for margin (documents go through Compress PDF instead).
• WhatsApp or email sharing — type 100–300 depending on the platform's practical limits.

Two byte-level details worth knowing: metadata (camera model, date, GPS) is stripped during re-encoding — which both protects your privacy and saves a few KB — and JPEG dimensions never change silently: if the tool had to scale pixels to reach an extreme target, the result line says so in plain numbers.

Where this fits in the form workflow

This tool handles images: photos, signatures, scans of certificates saved as JPG/PNG. For whole documents, use Compress PDF. And before you upload anything, run it through the Pre-flight Checker, which verifies size, pixels, format and background against your exam's compiled rules.