Interior Angle Balance Table
Balances closed-traverse interior angles against the (n-2)180 rule and distributes angular misclose.
Measured interior angles
- Angle 1°′″
- Angle 2°′″
- Angle 3°′″
- Angle 4°′″
- Angle 5°′″
Enter the angle at each station of the closed traverse. Runs in your browser — nothing is uploaded.
Balanced angles
| Station | Measured | Balanced |
|---|---|---|
| 1 | 108° 0' 30" | 108° 0' 26" |
| 2 | 107° 59' 50" | 107° 59' 46" |
| 3 | 108° 0' 40" | 108° 0' 36" |
| 4 | 108° 0' 10" | 108° 0' 6" |
| 5 | 107° 59' 10" | 107° 59' 6" |
The misclose is shared equally across all angles. Large misclose means a blunder — re-observe rather than adjust.
Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.
How to use this calculator
- Choose an angle format (DMS by default), then enter the measured interior angle at each station.
- Add a row per station around the closed traverse.
- Read the measured sum, the expected sum, the angular misclose and the balanced angles.
How it works
The interior angles of a closed polygon must sum to (n − 2) × 180°, where n is the number of angles. The difference between your measured sum and that target is the angular misclose.
The tool distributes the misclose equally across all the angles to give the balanced set used for the rest of the traverse computation.
Worked example
Five-sided traverse. Five interior angles should sum to (5 − 2) × 180° = 540°. If they sum to 540° 00′ 50″, the 50″ misclose is shared as −10″ per angle.
Frequently asked questions
When should I not just balance the angles?
Equal distribution assumes the small misclose is random. A large misclose points to a blunder (a mis-read or mis-booked angle) — find and re-observe it rather than adjusting it away.
Is this official course material?
No. It is free study support mapped to surveying course levels — not official North Metropolitan TAFE content or advice. Always follow your lecturer and the official assessment brief, and check your own working.
Related tools
- Exterior Angle Balance Table
- Latitudes and Departures Tutor
- Angular Misclose Calculator
- Basic Traverse Table Builder
- Traverse Closure Ratio Calculator
- Traverse Misclose Calculator
Explore more in Surveying, Coordinates, GIS & CAD.
Cite this tool
Zerdly. (2026). Interior Angle Balance Table. Retrieved from https://www.zerdly.com/tools/interior-angle-balance-table/
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.