Cable Cross-Section Calculator
Calculation by current and voltage drop check. Suitable for domestic 220/380 V lines.
System Parameters
Fill in the parameters — the result will update instantly
Approximate selection. For critical facilities, verify with IEC / local electrical codes.
| Cross-section, mm² | Cu 220 V, A | Cu 380 V, A | Al 220 V, A | Al 380 V, A |
|---|
Warning
The calculations provided are preliminary and intended for theoretical familiarization; they may also vary depending on the equipment specifications, project documentation, and operating conditions. The use of these data without additional verification is at the user's discretion.
Final technical solutions, specifications, and prices are determined after verification of the initial data and are documented separately (in a specification/contract). The company is not responsible for the consequences of using preliminary calculations without such verification.
Cable cross-section calculator online: precise wire cross-section calculation
Free tool for cable selection by power, current, and voltage drop — for 220/380 V networks
Our cable cross-section calculator helps you quickly perform a wire cross-section calculation for apartments, private houses, offices, and small commercial facilities. The service takes into account the current type (AC/DC), 1-phase or 3-phase system, cosφ, line length, installation method, and cable grouping. As a result, you get the minimum cross-section by current, voltage drop check in %, and the final recommendation in mm².
What the calculator can do
- Selection by power (kW) and calculated current (A) with correction for cosφ.
- Voltage drop check depending on the route length, material, and cross-section.
- Material selection: copper (Cu) or aluminum (Al) conductor with typical allowable currents.
- 220/380 V modes: single-phase and three-phase lines for domestic and small business use.
- Correction for installation conditions (exposed/concealed) and for grouping cables in a bundle.
When wire cross-section calculation is needed
Planning electrical installation, replacing old wiring, or connecting new consumers? The calculator will help select the cross-section for socket groups, lighting, electric stoves, boilers, air conditioners, charging stations, etc. The correct choice of cross-section increases safety, reduces energy losses, and ensures proper operation of circuit breakers.
How to use
- Specify the total power in kW or an estimate for the group.
- Select the material (copper/aluminum), line length, allowable voltage drop (usually 3–5%).
- For AC, set the phasing and cosφ (typically 0.95–1.00).
- Get the recommended cross-section in mm² and an approximate safety margin ratio.
Copper or aluminum cable?
Copper has a lower specific resistance and greater conductivity for the same cross-section, but aluminum is often more cost-effective for long lines of high power. In the results, you will see a comparison of allowable currents for Cu/Al, which simplifies the choice.
Important
The calculation is approximate and based on typical reference information. For critical facilities, we recommend verifying with IEC 60364 / local electrical codes and data sheets for specific cables, as well as taking environmental conditions into account.
Quick selection in a minute
AC/DC, cosφ, voltage drop
Approximate allowable currents
