Bulk image compressor

The three ways to compress a batch

Most bulk compressors give you one dial: quality. Set quality, hit go, hope the resulting files land where you need them to. That works for casual use. It fails the moment the byte target is a hard requirement — a form-upload cap, an email-attachment budget, a build-output size limit.

This tool gives you three modes so you can pick the right one for the job:

• Preset quality — pick from Web (quality 80), Email (quality 75, capped at 1280 px), Max quality (95, source dimensions), or Smallest (quality 50, 1280 px). Fastest mode. Best when the target is a rough guideline.
• Per-file KB target — every output file is iteratively re-encoded until it's under the KB target you set. Uses binary-search over quality, drops dimensions if quality alone can't hit the target. Best when every file has to satisfy a hard byte cap (form uploads, per-attachment email limits).
• Total ZIP budget — set an MB budget for the whole ZIP. The tool splits that budget across files proportionally to source size (a 5 MB source gets a bigger share than a 500 KB source), then iterates each file to fit its share. Best when the constraint is on the batch as a whole (CDN upload limits, backup archive size caps).

How this compares to TinyPNG's free tier

TinyPNG is the most-cited free bulk compressor. Its free tier caps at 20 files per batch, 5 MB per file, and 100 files per month. The paid tier lifts the file cap and monthly limits but keeps the batch cap. Neither tier has per-file byte targeting or total-batch budget targeting — you set an optimisation level and hope.

This tool has no batch cap (memory-limited, not policy-limited), no monthly cap (nothing counted, nothing uploaded), no per-file byte cap (25 MB per input for browser stability), and adds the two targeting modes above. Free, no signup, no watermark, no surveillance.

Related tools

• Compress a single image — same underlying compression, one file at a time with a live quality slider.
• Compress a single image to an exact KB target — the iterative logic used by the per-file mode above.
• Convert to WebP — often the easiest way to shave 25–35% before you even start compressing.
• How to compress images in bulk — the guide — deeper walk-through of when to use each target mode.
• How many images can I compress at once? — the memory-limit conversation in more detail.