Rontoampere is 1e-27 ampere units.
Rontoamperes to Femtoamperes Converter — rA to fA
Convert Rontoampere (rA) to Femtoampere (fA) using the exact conversion factor (1 rontoampere = 1e-12 femtoampere). See the formula, worked examples, and conversion table.
Rontoamperes to Femtoamperes converter
Converter
Electricity Converter
Convert electrical units by family and calculate voltage, current, resistance, power, and energy with context values.
Context values
Some unit families need one extra value for a physically accurate result.
Femtoampere is 1e-15 ampere units.
Result = input x 1e-27 / 1e-15.
Electrical units in the same family convert directly.
Reserved above the conversion cards and below the converter.
About Converting Rontoamperes to Femtoamperes
Rontoampere and Femtoampere both belong to the electricity family — voltage, current, resistance, power, or energy — units that show up constantly when working across the different standards used by household wiring (120V/240V depending on region), automotive electrical systems (12V/24V), and electronics design. Specifically: Rontoampere is 1e-27 ampere units, and femtoampere is 1e-15 ampere units.
Formula
femtoamperes = rontoamperes × 1e-12
This factor comes from each unit's defined relationship to the category's base unit: 1 rontoampere equals 1e-27 base units, and 1 femtoampere equals 1e-15 base units, so dividing one by the other gives the direct rontoampere-to-femtoampere factor of 1e-12.
Simple example
1 rA × 1e-12 = 1e-12 fA
1 rontoampere = 1e-12 femtoamperes.
Real-world example
120 rA × 1e-12 = 1.2e-10 fA
120 rontoamperes = 1.2e-10 femtoamperes.
Conversion table
| Rontoampere (rA) | Femtoampere (fA) |
|---|---|
| 1 rA | 1e-12 fA |
| 5 rA | 5e-12 fA |
| 12 rA | 1.2e-11 fA |
| 24 rA | 2.4e-11 fA |
| 120 rA | 1.2e-10 fA |
| 240 rA | 2.4e-10 fA |
Reverse conversion: Femtoampere to Rontoampere
1e-12 fA × 1e+12 = 1 rA
1e-12 femtoamperes = 1 rontoampere.
rontoamperes = femtoamperes × 1e+12
For a page dedicated to this direction, see Femtoampere to Rontoampere.
Understanding the Rontoampere (rA)
Rontoampere is 1e-27 ampere units.
Understanding the Femtoampere (fA)
Femtoampere is 1e-15 ampere units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many femtoamperes are in 1 rontoampere?
1 rontoampere equals 1e-12 femtoamperes, using the exact defined conversion factor rather than an estimate.
How do I convert rontoampere to femtoampere?
Multiply the rontoampere value by 1e-12. The converter above does this instantly to whatever precision you set.
How do I convert femtoampere back to rontoampere?
Use the reverse factor: 1 femtoampere equals 1e+12 rontoamperes. You can also use the swap control in the converter above to flip the direction instantly.
What is a rontoampere?
Rontoampere (rA) is a unit of electricity.
What is a femtoampere?
Femtoampere (fA) is a unit of electricity.
Is the rontoampere to femtoampere conversion exact?
Yes. Both rontoampere and femtoampere are defined by fixed standards rather than physical artifacts, so the factor of 1e-12 used above is exact to as many digits as you choose to display.
What's the difference between voltage, current, and resistance?
Voltage (volts) is the electrical potential difference driving current through a circuit. Current (amperes) is the rate of flow of electric charge. Resistance (ohms) is how much a component opposes that flow. They're related by Ohm's law (V = I × R), but they are distinct physical quantities, and this page converts between units of just one of them.