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Tools / Batch

Run any tool across a whole folder

Encode or Convert/Optimize multiple images at once, each processed by the exact same pipeline as the single-image tools. Errors on one file don't stop the rest. Download everything as a real ZIP archive when it's done.

Drop images here, or choose files
JPEG · PNG · WEBP · AVIF — multiple files supported

How Batch actually works

Each file in the queue gets processed by a dedicated Web Worker that calls the identical runEncode or runConvert functions the single-file Encode and Convert tools call — the same code, not a separate reimplementation, so behavior stays consistent whether you process one file or fifty.

Results are streamed back to the page as each file finishes — file-start, file-done — so the queue status updates live rather than waiting silently for the whole batch. Everything that succeeds gets packed into a real ZIP archive, built with an actual CRC-32 checksum table and DEFLATE compression via the browser's native CompressionStream, not a placeholder or a fake ".zip" wrapper around uncompressed files.

Cancellation is cooperative, not immediate: the worker finishes whatever file it's currently on, then stops before starting the next, so you never lose a result that was already most of the way done.

Questions people actually ask

What happens if one file in the batch fails?
It's marked failed in the queue, with the real error, and the rest of the batch keeps going. A single bad or corrupt file doesn't stop the others from processing, and the final ZIP includes everything that actually succeeded, with an honest success/fail count.
Can I cancel partway through?
Yes — Cancel finishes the file currently being processed (so you don't lose a partial result), then stops before starting the next one. The ZIP you get afterward contains whatever succeeded before the cancellation.
Is there a limit on how many files or how large a batch can be?
No artificial cap is enforced. The real limit is your browser's available memory, since every file is held and processed locally — very large batches or very large individual files may run into that ceiling, but there's no arbitrary count or size restriction built into the tool itself.
Does batch processing use different logic than the single-file tools?
No — it calls the exact same encode and convert functions the single-file Encode and Convert tools use, just once per file in the queue inside a dedicated worker. There's no separate, simplified batch-only code path that might behave differently.