Set your instrument, scale length, tuning, and gauges. Tap any string row to edit its note, gauge, and construction type. The live total tension and per-string feel colors update instantly.
Support
Tensora: String Tension Support
Help for version 1.4 — tension calculator, flatwound strings, Compare tab, Finder, Tuning Range, and more.
In the string editor, tap a string row and choose "Flatwound" (electric guitar) or "Bass Flat" (bass guitar) from the construction row. Tensora will recalculate tension using flatwound-specific unit weights — typically 7–18% higher than roundwound at the same gauge.
Tap the Compare tab (↔ icon), then tap the B slot to pick a saved setup. Tensora shows you total tension, average per-string tension, spread, and string-by-string deltas side by side. Useful for comparing a flatwound set against your usual roundwound setup.
Work backwards from a target tension. "One string" finds the closest gauge for a target lbf; "Balance set" suggests gauges for every string so the whole set pulls even tension. Both modes support all construction types including flatwound.
In the calculator, tap the share button (↑) in the top-right corner. A formatted text summary of your current setup — notes, gauges, construction, per-string tensions, total — is ready to send to Messages, Mail, Notes, or any other app.
The Range tab sweeps each string's pitch up and down ±1 octave to show where tension crosses from slack to comfortable to caution. Select a string from the tab at the top to inspect its safe tuning envelope.
Common Questions
What are flatwound strings and why do they have higher tension?
Flatwound strings wrap the core with a flat ribbon of wire rather than a round wire, leaving no gaps between windings. Because the flat ribbon fills in completely, flatwounds are heavier per inch than roundwounds of the same gauge — typically 7–13% heavier for electric guitar, and 11–18% heavier for bass. That extra mass produces more tension at the same pitch and scale length.
I switched from nickel wound to flatwound — why is the tension so much higher?
This is expected. Even at the same gauge, flatwounds pull more because they're denser. Use the Finder tab to find a lighter gauge that matches your target tension, or use the Compare tab to see exactly how much the tension changed string by string.
What are stainless wound strings?
Stainless steel wound strings are brighter and longer-lasting than nickel wound. Because stainless steel is denser than nickel alloy, the same gauge runs about 6.5% heavier per inch — producing higher tension. Use the Finder tab to find a gauge that hits your target tension with stainless.
How do I save a setup to compare it?
In the calculator, tap the save button (↓ cloud icon) in the top-right, give the setup a name, and tap Save. Your setup will appear in the Compare picker and the library sheet.
Does the app require an account or internet?
No. Tensora is fully offline. No account, no subscription, no network access.
Where is my data stored?
All setups and settings are stored locally on your device using UserDefaults. Nothing is sent anywhere.
Need help?
Email the App Store product page with your device model, iOS version, and a description of the issue.