Compress JPG images to an exact size — free, private, in-browser

Byte limits are enforced by the form before any human sees the file, and the error message rarely says which requirement failed. Hitting the number in advance is what turns a rejected upload into a completed application.

The compressor tests encoder settings against the requested byte window. Output size is not perfectly predictable, and some windows cannot be reached; read the result card and inspect the image.

Photographs of identity documents, signatures and marksheets are exactly the files that should not be handed to a stranger's server, and they are also the files that most often need compressing. Processing them in the tab removes that trade-off entirely.

This page is pre-set to 100 KB (1,02,400 bytes), which is the figure forms most often quote. Because the engine measures the encoded size after each pass rather than trusting a quality setting, the number you get back is the number in the result card and nothing else — the arithmetic behind it is on this page rather than hidden in a server.

Photographs from phones carry more metadata than most people realise — capture timestamp, camera model, the orientation tag that decides whether the picture displays upright, and often GPS coordinates precise to a few metres. Because every operation on this site writes a fresh file, that metadata does not survive by default. For a photograph of a marksheet or a bank statement, that is a privacy gain; for an archival photograph, note the date before you process it.

On a phone, memory is the real constraint rather than any size limit. A 12-megapixel photograph is about 36 MB once decoded into pixels, so compiling a batch of twenty and holding every result in memory at once will get a mobile browser killed well before it runs out of storage. Process batches of ten to fifteen on a phone; on a laptop the same job is unremarkable.

Accepted inputs are JPEG, PNG, WebP, AVIF, HEIC, GIF and BMP images up to 50 MB each. SVG, HTML and other script-bearing formats are refused outright rather than sanitised, because a file that can execute code has no business being re-encoded — and an upload field that accepts one is a security hole rather than a feature. Output is written as JPEG, matching the format the destination expects. Several files can be queued where the workbench supports it. Batch, page and memory limits apply; check every output.

Encoding is monotonic in quality — a higher setting always produces a larger file — which makes the size search a binary search rather than a scan. The engine predicts the working resolution from the ratio of the original's encoded size to your target, because byte count scales roughly with pixel count; that prediction is what keeps a 12-megapixel phone photograph down to a couple of seconds. If the target is unreachable at any quality, the dimensions are stepped down along a geometric ladder and the path taken is reported. Where a portal enforces a floor as well as a ceiling, standards-compliant padding — a JPEG comment segment or a PNG text chunk — adds bytes that no decoder renders, leaving every pixel untouched. The encoder writes a fresh image rather than editing the original in place, which means colour profile handling is consistent and metadata is dropped deliberately. Quality is chosen by measured search over the encoded output, so the number reported is the actual byte count of the file you are about to download — not an estimate from a table of typical sizes.