Detect whether a ZIP uses legacy ZipCrypto, AES-128, AES-192, or AES-256 encryption. Critical before sharing — ZipCrypto is broken and should be re-encrypted.
Per-job file size, entry count, and batch caps for Encryption Detector. Limits apply to every Archive tool in JAD Apps; upgrade for larger uploads and bigger batches.
| Tier | Max archive size | Max entries / archive | Max files per batch |
|---|---|---|---|
| Free | 47.7 MB | 500 | 1 |
| Pro | 476.8 MB | 50,000 | 20 |
| Developer | 1.86 GB | 50,000 | 20 |
Drop your encrypted ZIP
We inspect each entry's general-purpose flag bit 0 plus the AES-WinZip extra field (0x9901)
Get a per-entry breakdown: ZipCrypto / AES-128 / AES-192 / AES-256 / not encrypted
0 bytes uploaded. Encryption Type Detector runs entirely in your browser using fflate, zip.js, and libarchive WASM. Your archive files never leave your device.
ZipCrypto (legacy) has a known-plaintext attack — given any 12 known plaintext bytes, the password can be recovered in seconds. AES-256 is currently uncrackable. Always re-encrypt ZipCrypto archives with AES-256 before sharing sensitive data.
Yes — different entries can use different methods. The report flags this as it's a strong sign of an unfinished re-encryption or tampering.
Yes — both indicators (general-purpose bit 0 and the AES extra field) are present in plaintext metadata, not behind the encrypted payload. Detection is 100% reliable without needing the password.
Bundle files into a ZIP with WinZip-compatible AES-256 encryption. Powered by zip.js — your files and password never leave your device.
Open toolType a password and instantly verify whether it unlocks an encrypted ZIP — no full extraction required. Useful for retrieving forgotten passwords from a list.
Open toolInspect every entry's headers — version, OS, last modified, compression method, encryption flags, extra fields. Forensic-grade ZIP intelligence, zero upload.
Open tool