Gradians to Degrees Converter
Enter an angle in gradians to convert to degrees and radians.
Result
How it is calculated
A full circle is 400 gradians (gon) or 360 degrees, so the tool uses degrees = gon × 0.9 and radians = gon × π / 200. gon is the angle in gradians. Degrees are shown with two decimals and the degree sign, radians with four decimals. There is no range limit: negative angles and angles above 400 gon are converted as they are, without wrapping around to 0–360, so 450 gon returns 405.00°, not 45°. Anything that is not a number returns no result. Results are rounded for display only, so a long decimal in the input can show a rounded last digit.
Worked example
A surveying instrument reads 37.5 gon. Degrees: 37.5 × 0.9 = 33.75°. Radians: 37.5 × 3.14159 / 200 = 0.5890 rad. As a check, 37.5 gon is 37.5% of a right angle, and 33.75 is 37.5% of 90, so both agree.
Common mistakes
- Dividing by 0.9 instead of multiplying. One gon is smaller than one degree, so the degree value is always 10% less than the gon value.
- Confusing gon with grad as a unit on a calculator display. Many scientific calculators label the third angle mode GRAD; it is the same gradian, not a different unit.
- Expecting angles to wrap to a single turn. The tool gives 405° for 450 gon; subtract 360 yourself if you need the equivalent within one revolution.
- Reading a surveying bearing in degrees-minutes-seconds as a decimal degree. The tool takes decimal gon only.
- Using the radian output for a degree-mode calculation, or the reverse, which is the commonest cause of wrong trigonometry results.
Sources
- NIST Guide to the SI, Appendix B.8: Factors for Units Listed Alphabetically — NIST Special Publication 811
About this calculator
The gradian (gon) is an alternative angle unit that divides a full right angle into 100 equal parts instead of 90, making a complete circle equal to 400 gon. The conversion is a fixed ratio: 1 gon = 0.9 degrees (since 400 gon = 360°), and the same value can also be expressed in radians using the standard π/180 relationship applied to the degree equivalent.
Gradians were designed to simplify decimal calculations in land surveying and civil engineering — a right angle of exactly 100 gon avoids the fractional awkwardness of 90°. They still appear on many surveying instruments, in French and other European engineering traditions, and as a selectable angle mode on scientific calculators alongside degrees and radians.
Was this helpful?
You can pick up to 3 reactions.
Popular calculators
Loan Calculator
Monthly payment, total interest and full amortization schedule.
Percentage Calculator
Percent change, percent of, and ratio calculations.
Discount Calculator
Calculate final price, savings, and discount amount.
BMI Calculator
Body mass index from height and weight (metric or imperial).
Age Calculator
Compute your exact age in years, months and days from a birth date.
Compound Interest Calculator
Calculate the final amount and interest earned with compounding.
All Calculators
- Loan Calculator
- Profit Calculator
- Discount Calculator
- BMI Calculator
- Percentage Calculator
- Ideal Weight Calculator
- Age Calculator
- Pregnancy Due Date Calculator
- Compound Interest Calculator
- BMR Calculator (Basal Metabolic Rate)
- Tip Calculator
- Fuel Cost Calculator
- Date Difference Calculator
- Sleep Cycle Calculator
- Daily Water Intake Calculator
- Simple Interest Calculator
- Heart Rate Zones Calculator
- Running Pace Calculator
- Pet Age Calculator
- Calories Burned Calculator
- Macro Calculator
- TDEE Calculator (Total Daily Energy Expenditure)
- Waist-to-Hip Ratio Calculator
- Honor Roll Calculator
- One Rep Max (1RM) Calculator
- Ovulation Calculator
- Electricity Cost Calculator
- Unit Price Calculator
- Savings Goal Calculator
- Break-Even Point Calculator
- Paint Calculator
- Course Grade Average Calculator
- Business Days Calculator
- Time Duration Calculator
- Fuel Economy Calculator
- Temperature Converter
- Tile Calculator
- Aspect Ratio Calculator
- Roman Numeral Converter
- Goal Weight Timeline Calculator
- Salary Converter (Hourly to Annual)
- Credit Card Validator (Luhn)
- Body Surface Area (BSA) Calculator
- Feels-Like Temperature Calculator
- Ohm’s Law Calculator
- PPI (Pixel Density) Calculator
- Molar Mass Calculator
- Zodiac Sign Calculator (Western + Chinese)
- IBAN Validator
- Shoe Size Converter
- Country Info & Dialing Code Lookup
- Time Zone Difference (World Clock)
- CAGR (Compound Annual Growth Rate) Calculator
- Rule of 72 Calculator
- Blood Alcohol Content (BAC) Calculator
- Lean Body Mass (LBM) Calculator
- Pythagorean Theorem Calculator
- Speed Converter
- Download Time Calculator
- Date Calculator (Add/Subtract)
No calculators found
Comments (1)
Before you convert, check which angle mode your instrument is really in: a total station or calculator left in degree mode will show a right angle as 90, not 100. For a mental check, take a tenth off the gon value; 100 gon is 90 degrees. The tool gives decimal degrees only, so 33.75 is 33 degrees 45 minutes. What instrument or field do you meet gon in?