Peek inside any ZIP — list contents with sizes before extracting anything. Verify a 500 MB download's contents first — local fflate parsing, free, no signup.
Runs on fflate
Content reviewed October 2026 · About Toolzum
Extract CSV columns by name into clean lists. Pull email and name columns from pasted CSV in seconds — local parsing, free, no signup.
Convert lists between comma, newline, pipe, tab, semicolon, and space delimiters. Move data across tools without reformatting — free, local, no signup.
Convert ring sizes across US, UK, EU, and Japanese standards with millimeter diameters. Buy a size 7 as EU 54 correctly — free, local, no signup.
Read any PDF's metadata instantly — page count, size, author, creation date, encryption status. Verify a download before opening fully — local parsing, free, no signup.
Analyze HAR network captures — waterfall timing, payload sizes, failed requests. Find the 3-second render blocker in minutes — local parsing, free, no signup.
Yes — the archive lists every file with sizes instantly. A 500 MB download reveals its 40 files before you commit disk space or trust.
Standard ZipCrypto passwords work where supported; AES-256 archives may refuse — try the desktop 7-Zip for those. The tool says so upfront instead of failing mid-extract.
Hundreds of megabytes parse fine locally; gigabyte archives can strain mobile browsers — extract those on desktop. File count matters more than bytes: 5,000 tiny files list slower than one big video.
No — parsing and extraction run locally in your browser with fflate. Archive contents never leave your device.