# Compress ZIP

> Compress ZIP Archive (ZIP) files online for free. The compressor repacks every file at maximum compression; the contents are byte-identical. Processed in an isolated cloud sandbox and deleted automatically.

URL: https://www.converterrr.com/compress-zip

- Compression: lossless, runs in an isolated cloud sandbox (deleted automatically).
- API: `POST /api/v1/jobs` with `"operation": "compress"` (paid plans).
- Format: [ZIP converter](https://www.converterrr.com/zip-converter), [Compress archives](https://www.converterrr.com/compress-archives).

## What compression does to ZIP

Repacks every file at maximum compression; the contents are byte-identical.

It's lossless, so there are no quality levels: every file comes back with identical contents, just packed more tightly.

Need it much smaller? If the recipient can open 7z, it usually gets smaller still. [Convert ZIP to 7Z](https://www.converterrr.com/zip-to-7z).

## How to compress ZIP

1. **Add your ZIP files.** Drag and drop ZIP files onto the compressor, paste them, or click to browse. You can add several at once.
2. **Keep the default.** ZIP compression is lossless, so there's nothing to tune: every file comes back with identical contents.
3. **Compress.** Click Compress. Files are processed in an isolated cloud sandbox and are usually ready in seconds.
4. **Download.** Download each smaller ZIP, or everything at once as a ZIP.

## Good to know

- Every file is repacked at maximum compression, and extracts byte-for-byte identical to the original.
- Text, code, documents and uncompressed images shrink well; JPGs, MP4s and other already-compressed files inside barely change.
- Because ZIP compression is lossless, it can't be aimed at an exact size: the result depends entirely on what's in the file.
- ZIP files are compressed in an isolated cloud sandbox created just for your job; the upload and the result are deleted automatically afterwards.

## About the ZIP format

ZIP is the most widely supported archive format, bundling and compressing files so they open natively on Windows, macOS and Linux.

|  | ZIP |
| --- | --- |
| Full name | ZIP Archive |
| Type | Archive |
| Extensions | .zip |
| MIME type | application/zip |
| Best for | sending multiple files as one download |
| Properties | open standard |

## Compress other archives

[Compress 7Z](https://www.converterrr.com/compress-7z), [Compress TAR.GZ](https://www.converterrr.com/compress-tgz), [Compress TAR.BZ2](https://www.converterrr.com/compress-tbz2), [Compress TAR.XZ](https://www.converterrr.com/compress-txz)

## Compressing ZIP: frequently asked questions

### How do I compress a ZIP file?

Drop the ZIP onto the compressor above, and click Compress. Download the smaller ZIP when it's done; it usually takes a few seconds.

### Does compressing ZIP reduce quality?

No. ZIP compression is lossless. It repacks every file at maximum compression; the contents are byte-identical.

### How much smaller will my ZIP get?

Anywhere from almost nothing to a lot. ZIPs of text, code or uncompressed files made with fast settings shrink noticeably; ZIPs of photos, videos or other archives barely change.

### Can I compress ZIP to a specific size?

No. Because ZIP compression is lossless, the result depends on the content and can't be dialled to an exact number. If you need a much smaller file, converting ZIP to 7Z gets further.

### Is it safe to compress ZIP files here?

Yes. Your file travels over an encrypted connection to an isolated sandbox created for your job only, and both the original and the result are deleted automatically.

### Is the ZIP compressor free?

Yes. Cloud jobs like this one use the same free daily credits as cloud conversions, and there's no watermark.

### Should I convert my ZIP instead?

Sometimes. If the recipient can open 7z, it usually gets smaller still. The ZIP to 7Z converter does that in one step.