What is image compression?

Most of the weight in a JPEG photo is detail you will never miss: sensor noise, near-duplicate pixels, micro-detail that vanishes on a phone screen. This tool squeezes that weight out. You set two things — a target maximum file size in megabytes and a quality level — and the tool re-encodes your images accordingly, showing you exactly how much space you saved. Multiple images can be processed at once, with results available individually or bundled into a ZIP.

The target-size mode is the feature people actually need. Email attachments, marketplace listings, visa application portals, and CMS uploads all enforce size ceilings, and hitting an exact ceiling by hand-tweaking quality sliders is tedious. Set the ceiling, let the encoder do its work, done. Quality mode is for when file size is secondary: a quality around 80 is a well-established sweet spot that typically cuts file size by 60–80% with no visible difference on screen.

Compression happens entirely within your browser — the photos are decoded and re-encoded on your own device, never uploaded. For personal photos, scanned documents, or anything sensitive, that is the difference between using the tool and not using it.

A few honest caveats. JPEG compression is lossy: each save discards detail permanently, so compress from the original rather than re-compressing an already-compressed copy, which stacks artifacts. Images with hard edges and flat color — screenshots, logos, line art — compress poorly in JPEG and may show blockiness around text; PNG-oriented workflows suit those better. And extreme targets have a limit: a 12-megapixel photo cannot reach 50 KB without becoming visibly mushy, so keep expectations proportional to the source.