How to use the Create 7Z
- Add the documents, or drop the folder that holds them.
- Keep the preselected Maximum level or pick another; add a password under More settings if needed.
- Click Create and save the .7z file.
Smaller than ZIP, less universal
ZIP's Deflate only looks back 32 KB for repeated data. LZMA2 looks much further, so recurring letterheads, clauses and log lines across a folder are stored far more efficiently. On text-heavy folders a 7Z often comes out 30 to 50 percent smaller than a ZIP; on JPG scans and video the two are nearly equal.
In exchange, fewer recipients can open it with a double-click. Windows 11 recently gained 7Z reading, a Mac takes a free extractor like Keka or The Unarchiver, and on phones an app is normally required. For a one-off email to a client, ZIP is kinder.
Locking the archive, names included
A password turns on AES-256 encryption for the contents and the header together. Without the password nobody sees how many documents there are, what they are called or how large they are, which matters for HR files and legal bundles.
A forgotten 7Z password cannot be recovered except by guessing. Keep it in a password manager before you delete the originals.
Picking the level
Store only skips compression and is handy when encryption is all you want. Fastest and Fast are quick, Normal matches 7-Zip's own default, and Maximum or Ultra spend more time for the final few percent. Ultra can take several times longer than Normal, since 7-Zip runs on a single thread in this page.
The level changes only the effort of the encoder; any program that reads 7Z opens the result regardless.
Questions
Can it split the archive into parts?
No. The page always writes a single .7z file.
Is 7Z a sensible format for record keeping?
Yes. It is an open, documented format with free extractors everywhere, and stored CRC checksums reveal any corruption when the archive is opened later.