JustUtils
shield_lockLinux permissions 路 explained as you click

Chmod 775 Explained & Calculator

See how chmod 775 shares a directory with a group, verify every permission, and copy a complete Linux command.

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 路 7

rwx

Usually you or the account that created it.

Group permissions

Group

digit 2 路 7

rwx

Accounts collected in the file's owning group.

Everyone else permissions

Everyone else

digit 3 路 5

r-x

Any other account on the same system.

YOUR RESULT

775rwxrwxr-x

u=rwx,g=rwx,o=rx

Owner

Can list names, add or remove items, enter

Group

Can list names, add or remove items, 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_forward775
addOwner: executeaddGroup: writeaddGroup: 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鈥攊t 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 路 u

Owner

Usually you or the account that created it.

DIGIT 2 路 g

Group

Accounts collected in the file's owning group.

DIGIT 3 路 o

Everyone else

Any other account on the same system.

Chmod 775 in practice

How to decide whether 775 fits your directory

Mode 775 gives full access to the owner and owning group, while everyone else can read and traverse. It supports collaborative directories only when ownership and group membership are already correct.

Owner
7 = read + write + execute
The owning account can browse and manage directory entries.
Group
7 = read + write + execute
Group members can also create, rename, and remove entries in the directory.
Everyone else
5 = read + execute
Other local accounts can browse but cannot create or remove entries.

A practical example

A shared project directory for a deployment team

Several trusted deployment accounts belong to the same project group and need to update a shared release directory. Mode 775 can allow the group to collaborate while preserving read-only access for other accounts that must inspect the files.

Before saving the change

  • Verify the directory's owning group with ls -ld and review the group's members.
  • Consider the setgid bit so newly created items inherit the project group.
  • Check the team's umask because new files may otherwise lose group write permission.

Common mistake to avoid

Mode 775 alone does not guarantee smooth collaboration. New files can receive a different group or restrictive mode, and any group member may remove another member's directory entries.

When to choose something else

Choose 770 when outsiders should not browse the project. Choose 755 when only the owner should deploy. Consider setgid, a suitable umask, or ACLs for a durable team workflow.