Zip Files Online — In Your Browser, Free, No Upload
Updated June 2026 · Covers zip files online, zip a folder, compress to zip, no-upload zipping
Email attachment too big. A folder of 200 photos won't fit in one upload. A client portal that only accepts a single file. The fix is almost always the same: zip everything into one archive. This page walks through how to do it in your browser — no upload, no signup, no per-file size cap — plus when each compression level is worth picking.
How to zip files online
- Open the tool. Visit essexsoftware.com/zip-files-online. Loads in any modern browser; no signup or extension.
- Drop your files. Drag one file or a folder of many onto the dropzone. There's no per-file size cap and no batch cap.
- Pick a compression level (in Bulk Archiver). Balanced is the default and is fine for almost everything; the section below covers when to deviate.
- Click Create ZIP. The .zip is built in your browser and downloads to your device. Your originals are untouched.
Open the full tool
Need extract, password-protect, folder-mode, or custom filename? Bulk Archiver covers it all.
Which compression level to use
ZIP supports four practical compression levels. The right one depends on what's inside the archive:
| Level | When to use | What to expect |
|---|---|---|
| None (store only) | JPGs, PNGs, MP4, MP3, PDFs, other ZIPs — anything already compressed | Same size as input. Finishes fast — no CPU spent trying to compress data that won't compress. |
| Fast | Mixed content where speed matters | 5–15% smaller than input for typical mixed content. 2–3× faster than maximum. |
| Balanced (default) | Most everything else | The sweet spot. Text and documents drop 50–80%; mixed content drops 10–30%. |
| Maximum | Big text files, CSV, JSON, source code, logs | 10–30% better than balanced for text; only a few percent better on mixed content. Slower. |
The shortcut. If your files are 90%+ photos or video, pick None. If they're documents or text, pick Maximum. Otherwise Balanced is correct.
Zip a whole folder
Dragging a folder is supported on desktop Chrome, Edge, Firefox, and Safari — the relative folder structure is preserved inside the .zip. Empty folders are skipped. On mobile, the OS only exposes individual files through the share sheet, so you'd select multiple files manually instead of dragging a folder.
If you have a complex folder with thousands of files, the browser may take a couple of seconds to enumerate everything before the dropzone reacts. That's the OS reading the directory tree, not an upload.
How this compares to ezyzip, ilovezip, archive.online, others
| Feature | Us (in-browser) | Typical online zip tools |
|---|---|---|
| Files leave your device? | No — local only | Yes — uploaded to server |
| Free tier size cap | None (browser RAM is the limit) | Usually 500 MB – 2 GB |
| Batch / number of files | Unlimited | Often capped at 20–100 files |
| Signup required | No | Often, after first use |
| Works offline (after page load) | Yes — disconnect Wi-Fi to verify | No |
| Speed for large folders | Limited only by your CPU | Upload + download round-trip dominates |
FAQ
How do I zip files online without uploading them?
Use a browser-based tool that does the zipping in JavaScript or WebAssembly. The files never leave your device — your browser builds the .zip locally and hands you the result. You can verify by disconnecting from Wi-Fi after the page loads; the tool keeps working. Most popular online zip tools, by contrast, do upload your files to a server and zip them there.
What's the maximum file size I can zip online?
When the work happens in your browser, the limit is your device's RAM, not a server quota. Modern desktops handle multi-gigabyte archives without issue; phones are more limited (usually a few hundred MB before the tab gets killed). Tools that upload to a server typically cap the free tier at 500 MB or 2 GB.
Can I zip a whole folder, not just individual files?
Yes. Drag the folder onto the dropzone (in Chrome, Edge, Firefox, or Safari on desktop) and the relative folder structure is preserved inside the .zip. On mobile, the OS only exposes individual files, so you'd select multiple files manually.
Do I need to install anything?
No. The tool runs entirely in the browser tab — no extension, no signup, no download. The zip is built with WebAssembly DEFLATE that's loaded as part of the page.
What compression level should I use?
For text (CSV, JSON, source code, .docx, .xlsx), maximum gives 10–30% extra savings over balanced. For already-compressed files (JPG, PNG, MP4, MP3, PDF), no compression level helps much — the data is already compressed. In those cases, pick "None (store only)" to skip CPU work and finish faster.
What .zip format does this create?
Standard PKZIP with DEFLATE compression and ZIP64 extension when needed. Opens with macOS Archive Utility, Windows Explorer, 7-Zip, WinRAR, WinZip, and every other archive tool. Not RAR or 7z — those formats are separate.