Quick Answer

RADIANS Function

Converts degrees to radians.

✓ Excel✓ Google SheetsExcel All versions

Syntax

RADIANS
(angle)

Parameters

ParameterDescriptionRequired
angleThe angle in degrees that you want to convert to radians.Required

Basic Example

Convert 180 degrees to radians

=RADIANS(180)
Result3.141592654

180° equals π radians, about 3.14159.

Advanced Examples

Example 1: Convert 90 degrees

A quarter turn.

Pass 90.

=RADIANS(90)
Result: 1.570796327
90° is π/2 radians, about 1.5708.

Example 2: Convert 45 degrees

Common angle for trig.

Pass 45.

=RADIANS(45)
Result: 0.785398163
45° is π/4 radians, about 0.7854.

How RADIANS Works

RADIANS multiplies the degree value by π/180 to produce the equivalent radian measure. It is the inverse of DEGREES.

1
Select the cell
Click the cell for the radian result.
2
Enter the formula
Type =RADIANS(angle_in_degrees).
3
Press Enter
The radian value appears.

Important Notes & Limitations

  • It only converts degrees to radians, not the reverse (use DEGREES for that).

  • Results are floating-point approximations.

Common Errors & Fixes

#VALUE!Non-numeric argument.

Fix: Supply a numeric angle in degrees.

Download Practice File

Practice RADIANS with Real Data

Download a sample CSV file with pre-populated data and practice exercises for the RADIANS function. Works in both Excel and Google Sheets.

Works in Google SheetsCompatible with ExcelIncludes exercises

File format: CSV (comma-separated values) - opens in Excel, Google Sheets, and all spreadsheet apps

Frequently Asked Questions

What formula does RADIANS use?
radians = degrees × π / 180.
Why convert to radians at all?
Excel's trigonometric functions (SIN, COS, TAN) expect angles in radians.
How do I go back to degrees?
Use DEGREES(radians), which multiplies by 180/π.