JustUtils
shield_lockLinux permissions · explained as you click

Chmod, without the guesswork.

Choose who can read, change, or use an item. We translate every click into the three digits, explain the result, and build the command for you.

STEP 1

What are you changing?

Execute means different things for a file and a directory.

For a directory: Read lists names, Write adds or removes items, and Execute lets someone enter the directory and reach items inside.

STEP 2

Choose access

Owner permissions

Owner

digit 1 · 7

rwx

Usually you or the account that created it.

Group permissions

Group

digit 2 · 5

r-x

Accounts collected in the file's owning group.

Everyone else permissions

Everyone else

digit 3 · 5

r-x

Any other account on the same system.

YOUR RESULT

755rwxr-xr-x

u=rwx,g=rx,o=rx

Owner

Can list names, add or remove items, enter

Group

Can list names, enter

Everyone else

Can list names, enter

THE PART MOST CALCULATORS SKIP

See what will actually change

Find the numeric mode with stat -c '%a' path on Linux, then review each permission being added or removed.

644arrow_forward755
addOwner: executeaddGroup: executeaddEveryone else: execute

TOP 5 EVERYDAY MODES

Start from the job, not the digits

Each common mode has its own explainer page and loads directly into this calculator. Pick the situation that sounds like yours, then check the access before copying.

folder_open755

Public directory or script

You control it; everyone else can open or run it.

description644

Regular file

You can edit it; everyone else can read it.

key600

Private or secret file

Only you can read or edit it.

lock700

Private directory or script

Only you can open, change, or run it.

group775

Team directory

You and your group can edit; everyone else can browse.

CHMOD IN ONE MINUTE

What is chmod?

Every Linux file carries a tiny access list. chmod is the command that rewrites that list. It does not move the file, change its contents, or choose its owner—it only changes what the owner, group, and everyone else are allowed to do.

Think of the three digits as three keycards. The first card belongs to the owner, the second to the group, and the third to everyone else. Each card gets points for Read (4), Write (2), and Execute (1). Add the allowed actions to get that card's digit.

The only math you need

4Read+2Write+1Execute=7all three
Why 777 is not a universal fix: it hands every keycard every permission. Fix ownership or choose the smallest access that solves the real need instead.

DIGIT 1 · u

Owner

Usually you or the account that created it.

DIGIT 2 · g

Group

Accounts collected in the file's owning group.

DIGIT 3 · o

Everyone else

Any other account on the same system.