Example 1
V = 10<sup>6</sup> V.
Electric Potential Calculator
Type work W [J] and charge q [C]. The calculator computes V = W/q: 0.01 J on 2e-6 C is 5000 V, and 1 J on 1e-6 C is 1,000,000 V. Zero coulombs does not divide.
Field: E = F/q. Capacitance: C = Q/U.
Result
Energy W (J) and Charge q (C). The result shows up here.
How it works
Potential is work per charge: V = W/q. One volt is one joule per coulomb. At 0.01 J and 2 µC (2e-6 C) you get 5000 V. At 1 J and 1 µC you get 1e6 V, or 1 MV. At 1e-4 J and 1 nC you get 100,000 V.
The form has two fields: W in joules and q in coulombs. The result is in volts. Type 1 µC as 1e-6, not as 1. A comma, a period, and 1e-6 mean the same q. 0.01 or 1e-2 is the same work.
q must not be zero, because you do not divide by zero. Typed 0 in q is rejected. Zero joules at nonzero q gives V = 0. Both fields need a number before 5000 V appears.
E = F/q is on the neighbouring page and computes field strength in N/C or V/m, not potential in volts. C = Q/U is capacitor voltage from charge, a different formula. W = U I t on electrical work computes joules from a circuit; here W is an input.
A negative q gives negative V: charge sign. This calculator does not know distance from a source charge. It already takes W and q.
Type 0.01 and 2e-6, click Calculate, and check 5000 V. Then 1 and 1e-6: 1,000,000 V. The calculator divides W by q; it does not guess an electrode.
How to use
- In the first field enter W in joules, for example 0.01.
- In the second field enter q in coulombs, for example 2e-6. 1 µC is 1e-6, not 1.
- Click Calculate. 0.01 J and 2 µC give 5000 V. 1 J and 1e-6 C give 1,000,000 V.
- q = 0 is rejected. Zero in W at nonzero q gives V = 0. Both fields need a number.
- For E = F/q, open field strength. Capacitor C = Q/U is a different page.
Formula
V = W / q
Units: V = J/C. q ≠ 0.
V, W, and q on the potential card
Potential is work per charge: V = W/q. 0.01 J on 2e-6 C is 5000 V. 1 J on 1e-6 C is 1,000,000 V.
- V
- Potential [V]. 1 V = 1 J/C. 0.01 / 2e-6 = 5000 V.
- W
- Work to move q [J]. Not electric work U·I·t.
- q
- Test charge [C]. q = 0 does not divide. 2e-6 C at 0.01 J.
Real-life examples
Example 2
q = 2e-6 C -> V = 5000 V.
Example 3
W = 1e-4 J, q = 1e-9 C.
Example 4
q = 5e-6 C.
Example 5
W = 2 J, q = -4e-6 C.
Example 6
W = 9e-3 J on q = 1e-6 C.
Example 7
q = 1e-4 C -> V = 10<sup>6</sup> V.
Example 8
Same joules as kinetic energy.
Example 9
q = 1e-7 C.
Example 10
Fixed W = 5 J, q = 2e-6 C.
Ways to use this calculator
- You compute 5000 V from 0.01 J and 2 µC.
- You check 1 J on 1 µC: 1 MV.
Frequently asked questions
How much V at 0.01 J and 2e-6 C?
Potential is 5000 V. You divide 0.01 J by 2 µC. That is 1 V = 1 J/C, only the numbers here are small.
How much at 1 J and 1e-6 C?
You get 1,000,000 V, or 1 MV. One joule on a microcoulomb is a megavolt.
Which units do I type?
Work W [J], charge q [C]. Result V [V]. Type 1 µC as 1e-6, not as 1.
How is this different from E = F/q?
Here potential V [V] from work and charge. There field strength E [N/C] from force and charge. Different quantity, even though both divide by q.
Is this capacitor U = Q/C?
No. Here V = W/q from work on a charge. U = Q/C lives on the capacitance page, from charge and C.
Does a comma in 0.01 work?
Yes. 0.01 and 0,01 are the same W [J]. 1e-2 is also fine.
Where is W = U I t?
On the electric-work page. There joules from volts, amperes and time. Here W is an input to V = W/q.
Do I type 1 for 1 µC?
No. Field q wants q [C]. 1 µC is 1e-6 C. A bare 1 would make V a million times too small.
What about q = 0?
The calculator refuses zero coulombs. V = W/q at zero charge does not exist.
How much at 1e-4 J and 1 nC?
Potential is 100,000 V. 1e-4 / 1e-9. That is 0.1 MV on a nanocoulomb.
Knowledge sources
The formula is the school one. Units follow SI; NIST SP 330 and BIPM define the measures, not your result.
Page updated in 2026.