How to password tester vs unzip -t, 7z t, and openssl
- Step 1Pick the right job — Use this tool to verify one ZIP password fast. For 7z/RAR password testing or wordlist brute-forcing, stay on the CLI — those are out of scope here.
- Step 2
- Step 3Drop the ZIP — Drag a single
.zip. This is the browser equivalent of pointingunzip/7zat a file, but nothing is uploaded. - Step 4Type the candidate — Enter the password in the masked field — the equivalent of
-P 'pass'(unzip) or-p'pass'(7z), without the shell-history and quoting footguns. - Step 5Run and read the verdict — Get
correct/incorrect/error:/no encrypted entries found in archive— analogous to a CLI exit code, but as plain words plus a tested-entry name. - Step 6Escalate if needed — If the archive may be damaged, run archive-integrity-tester (the full
-tequivalent) or corrupted-zip-repair.
Password Tester vs common CLI approaches
What each approach actually does when you want to check a ZIP password. Exit-code behavior is the typical Info-ZIP / p7zip behavior.
| Approach | What it tests | Speed on a 4 GB ZIP | Privacy | Install |
|---|---|---|---|---|
| JAD Password Tester | Decrypts the first encrypted entry only — confirms the typed password | Milliseconds (one entry) | Local, nothing uploaded | None (browser) |
unzip -P 'pass' -t | Decrypts and CRC-verifies every entry | Minutes (full archive) | Local | Info-ZIP unzip |
7z t -p'pass' | Tests integrity of all entries with the password | Minutes (full archive) | Local | p7zip / 7-Zip |
openssl enc -d | Wrong tool — ZIP encryption is not OpenSSL's enc format | N/A | Local | OpenSSL |
for pw in $(cat list); do ... | Brute-force over a wordlist (a different task) | Hours to forever | Local | Shell + unzip |
Verdict mapping vs CLI exit codes
How this tool's verdict strings line up with the familiar CLI signals.
| This tool's verdict | unzip equivalent | 7z equivalent | Meaning |
|---|---|---|---|
correct | exit 0, no 'incorrect password' | 'Everything is Ok' | Password unlocks the first encrypted entry |
incorrect | 'incorrect password' / exit 82 | 'Wrong password?' | Password/CRC mismatch |
error: <msg> | exit 2/3 (read/format error) | non-zero, not a password error | Failure unrelated to the password |
no encrypted entries found in archive | no -P needed | no -p needed | Archive has no encrypted entries |
Cookbook
The same task done both ways, so you can see when the browser tool is faster and when the CLI is the right call.
Fast verify vs full unzip -t
On a large archive, the CLI verifies every entry; the browser tool checks one. Both answer the same question — is the password right.
# CLI (decrypts every entry — slow) $ time unzip -P 'Pass#2026' -t backup.zip ... 30,000 entries ... No errors detected. real 2m41s # JAD tester (first encrypted entry only) Verdict: correct Tested entry: db/dump.sql (elapsed: under a second)
Wrong password, both agree
A mismatched password reads as 'incorrect' in the browser and as exit 82 / 'incorrect password' on the CLI.
$ unzip -P 'wrong' -t client.zip skipping: README.txt incorrect password # JAD tester Verdict: incorrect Tested entry: README.txt
Using openssl is the wrong tool
ZIP encryption (ZipCrypto / AES) is not OpenSSL's enc format. Reaching for openssl produces a bad-magic error, not a verdict.
$ openssl enc -d -aes-256-cbc -in secret.zip -k pass bad magic number # JAD tester (correct tool) Verdict: correct
Brute-forcing is out of scope
A wordlist loop is a cracker, not a verifier. This tool tests the one password you type — by design.
# CLI brute-force (a different task; can run for hours) for pw in $(cat rockyou.txt); do unzip -P "$pw" -t archive.zip >/dev/null 2>&1 && echo "FOUND: $pw" done # JAD tester does NOT do this — one typed password per run.
No CLI installed? Browser still works
On a locked-down machine with no unzip/p7zip, the browser tool needs nothing installed.
$ unzip -P 'pass' -t a.zip bash: unzip: command not found # JAD tester (no install required) Verdict: correct / Tested entry: data.csv
Edge cases and what actually happens
Archive is 7z or RAR
Unsupported formatThe CLI (7z t) handles these; this tool does not — zip.js reads ZIP only. For 7z/RAR password checks, stay on 7z/unrar.
You need to verify every entry, not just one
Use the CLIunzip -t / 7z t CRC-check the whole archive. This tool checks only the first encrypted entry. For full-archive integrity in the browser, use archive-integrity-tester.
Brute-force / wordlist attack
Out of scopeThis is a verifier, not a cracker. A CLI loop or a dedicated cracking tool is the right approach for wordlist attacks — but this tool will never do it.
Password contains shell-special characters
Browser winsOn the CLI, $, backticks, and quotes in -P/-p cause quoting bugs and leak into shell history. The browser's masked field takes the literal string — no escaping needed.
openssl used to 'decrypt' a ZIP
Wrong toolZIP encryption is not OpenSSL's enc format. openssl reports bad magic. Use this tester or unzip/7z instead.
Empty password submitted
RejectedThe tool throws Enter a password to test. Unlike a shell loop, it will not silently try a blank password.
Mixed plaintext + encrypted entries
ExpectedThe tool tests the first encrypted entry. unzip -t would report 'No errors' for plaintext entries even without a password, which can mislead — the tester is unambiguous about what it verified.
Archive exceeds tier limit
413 too largeThe free tier caps at 50 MB / 500 entries. A huge multi-gig archive that the CLI handles locally may need a paid tier here (up to 2 GB / 500,000 entries).
Different unzip/p7zip versions disagree
Browser is consistentInfo-ZIP, macOS ditto, and p7zip can differ on AES handling and exit codes. zip.js behaves identically across browsers and OSes.
Correct verdict but CLI extract fails
PreservedA correct verdict means the first entry decrypts. If a specific CLI version still fails to extract, the issue is that tool's format support, not the password.
Frequently asked questions
Is this faster than unzip -P -t?
On large archives, yes — unzip -t decrypts and CRC-checks every entry (minutes on a multi-gig ZIP), while this decrypts only the first encrypted entry to confirm the password (milliseconds). Both answer the same question.
Does it test the whole archive like 7z t?
No. It verifies the password against the first encrypted entry. For full-archive integrity in the browser, use archive-integrity-tester, which is the closer analog to -t.
Can I use it on 7z or RAR like the CLI?
No. It reads ZIP only (via zip.js). For 7z/RAR password verification, use 7z t or unrar t on the command line.
Why not just use openssl?
ZIP encryption (ZipCrypto / AES-in-ZIP) is not OpenSSL's enc format. openssl will report a bad magic number. Use this tool or unzip/7z for ZIP passwords.
Can it brute-force a wordlist like a shell loop?
No. It tests one password per run — the one you type. Wordlist attacks are a different task and are out of scope.
What's the equivalent of an exit code here?
The verdict field: correct (≈ exit 0), incorrect (≈ 'incorrect password'/82), error: (≈ a read/format error), and no encrypted entries found in archive.
Does my file get uploaded like some online tools?
No. Everything is local in your browser. Unlike sharing an archive to a remote service, the file and password never leave your machine.
Is the output script-friendly?
Yes — it emits JSON { filename, testedEntry, verdict }, easier to parse than scraping unzip/7z text output and remembering exit codes.
How do I handle a password with special characters?
Type or paste it into the masked field as-is. There is no shell to escape $, backticks, or quotes for, and nothing lands in shell history.
What if I have no CLI tools installed?
This needs nothing installed — it runs in the browser. On locked-down machines where unzip/p7zip are missing, it still works.
Is behavior consistent across OSes?
Yes. zip.js behaves the same in every browser, unlike the variation between Info-ZIP, macOS, and p7zip builds.
When should I still prefer the CLI?
When you need 7z/RAR support, a full every-entry integrity test, brute-forcing, or you're already scripting batch jobs locally. For a quick 'is this the right password' on a ZIP, the browser tool is faster and zero-setup.
Privacy first
Every JAD Archive tool runs entirely in your browser using fflate, @zip.js/zip.js, and the libarchive WASM bridge. Your archives never leave your device — verified by zero outbound network requests during processing.