CATCH THE WRONG UNIT IN THE FORMULA

Unit Equation Checker

Calculate formulas with mixed units and check dimensional consistency. Convert variables to SI, inspect calculation steps and export a unit-aware result report.

Mixed SI and common US unitsSeven-dimension consistency checksReadable calculation trace

Start with the worked example. Results update when you leave a field or select an option.

From a real task to a useful result

Who this helps

For students, makers and developers checking physical calculations.

Try this example

Enter voltage = 12 V and current = 250 mA. voltage * current produces 3 W. Adding a distance in meters to a duration in seconds is rejected with a dimensional mismatch.

Scope and limits

40 variables, 256 expression tokens and 64 nested levels. Supported units are listed in the tool. Multiplication must use *. Temperature offsets, symbolic solving, uncertainty propagation and arbitrary prefixes are unsupported. Calculations use floating-point arithmetic.

Further reading: NIST guide to SI dimensions and quantities.

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Using Unit Equation Checker

Calculate formulas with mixed units and check dimensional consistency. Convert variables to SI, inspect calculation steps and export a unit-aware result report.

Enter variables as name,value,unit CSV or start from an energy, length or electrical example.
Write the formula with explicit multiplication, powers and parentheses. Use the unit reference for supported symbols.
Optionally choose an output unit. Review mismatches or the converted result and SI dimension signature.
Inspect each calculation step, then download the report, trace CSV or dimensional diagram.

Example

Enter voltage = 12 V and current = 250 mA. voltage * current produces 3 W. Adding a distance in meters to a duration in seconds is rejected with a dimensional mismatch.

Questions & answers

Does dimensional consistency prove my formula is correct?

No. It catches incompatible dimensions and output units, but a physically incorrect formula may still be dimensionally consistent.

Can I mix inches, centimeters and meters?

Yes. Supported units are converted to SI before operations. Compatible dimensions can be added or subtracted regardless of their original scale.

Why do C and F not mean temperature?

C is coulomb and F is farad in this tool. Only kelvin K is supported for temperature quantities; Celsius and Fahrenheit offsets need a separate converter.

Which functions and unit conventions are supported?

sqrt, abs, sin, cos, tan, natural log and exp. Angles are dimensionless with deg converted to radians. Unit symbols are case-sensitive; direct variables take precedence over units of the same name.

Can I keep my work for later?

Save project downloads your inputs and settings as JSON. Open project restores them. Undo and redo are available during this tab session; there is no automatic project save.