Symbolic Permission Calculator
Convert symbolic permission strings like rwxr-xr-- into octal chmod values.
About Symbolic Permission Calculator
Symbolic permissions (the rwxrwxrwx string from ls -l) map directly to octal: each triplet (owner, group, others) converts by summing r=4, w=2, x=1. Special bits (SUID=4, SGID=2, sticky=1) form an optional leading digit. This calculator converts the human-readable ls -l output to the numeric form needed for chmod commands.
Formula
Triplet to octal
octal_digit = (r?4:0) + (w?2:0) + (x?1:0)
- r
- read bit present
- w
- write bit present
- x
- execute bit present
Worked example
With the default values below, Symbolic Permission Calculator returns Octal Permission of 754. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Symbolic Permission String
- rwxr-xr--
Results
- Octal Permission
- 754
- chmod Command
- chmod 754
- Owner
- 7
- Group
- 5
- Others
- 4
- Special Bits
- 0
Step by step
- 1Owner triplet= 7
- 2Group triplet= 5
- 3Others triplet= 4
- 4Special bits= 0
- 5Octal result= 754
Assumptions and limits
- The result is derived only from the single input listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
What does 's' mean in a permission string?
Lowercase 's' in the owner's execute position means SUID is set AND execute is set. In the group position it means SGID+execute. Uppercase 'S' means the special bit is set but execute is NOT — which is usually a mistake.
What does 't' mean in the others position?
The sticky bit ('t' when execute is also set, 'T' without execute) on a directory means only the file owner, directory owner, or root can delete files within it — the classic example being /tmp with permissions 1777.