Enter a string gauge, scale length, and target frequency to estimate the string’s tension in pounds.
String gauge (thousandths of an inch):
Scale length (inches):
Target pitch frequency (Hz):
How It Works
The calculator uses the standard string tension formula based on unit weight (derived from gauge and steel density), scale length, and target frequency, giving an estimated tension in pounds.
How to Use This Tool
- Enter the string gauge in thousandths of an inch (for example, a high E string is often .010).
- Enter your instrument’s scale length, or leave the standard 25.5″ default.
- Enter the target pitch’s frequency in Hz and click Calculate.
This estimate is most accurate for plain steel strings; wound strings have a different effective unit weight per gauge and will actually pull somewhat higher than this estimate.
Did You Know?
- Total tension across all six strings of a standard-tuned acoustic guitar is often well over 150 pounds combined.
- Heavier gauge strings generally have more tension at the same pitch, which is part of why they can feel stiffer to fret.
Frequently Asked Questions
Does this work for bass strings?
The formula applies the same physics, but bass strings are almost always wound, so the plain-steel estimate here will read lower than the actual tension.
How do I find my note’s frequency in Hz?
Use the site’s Note & String Frequency Converter to look up the exact Hz for any note before entering it here.