# MyElectricCalculator.com > Free, browser-based electrical-trade calculators and unit converters for > conductor sizing, load planning, overcurrent protection and power conversion — > built for electricians, contractors, solar installers and engineering > students. Every tool prints the code table or formula it works from, so the > answer can be checked rather than trusted. Every calculation runs client-side in the browser. Nothing you type is uploaded, there is no account, and there is no tracking script. Each calculator works from a table transcribed out of a published wiring standard — NFPA 70 (NEC), BS 7671 or AS/NZS 3000 — and every constant in the source carries a comment naming the table or rule it came from. These are planning and estimation tools. They are not a substitute for the current, complete text of the NEC, BS 7671 or AS/NZS 3000, for the amendments a particular jurisdiction has adopted, or for review by a licensed electrician or the Authority Having Jurisdiction. ## Sizing & Selection - [AWG Wire Size Calculator](https://myelectriccalculator.com/calculators/awg-calculator/): Convert between AWG, kcmil and mm², and find the conductor area for a given size. - [Transformer Sizing Calculator](https://myelectriccalculator.com/calculators/transformer-sizing-calculator/): Standard kVA for a connected load, plus primary and secondary full-load current. - [Grounding Conductor Size Calculator](https://myelectriccalculator.com/calculators/grounding-conductor-size-calculator/): Grounding electrode conductor from 250.66, or equipment grounding conductor from 250.122. - [Wire Size Calculator](https://myelectriccalculator.com/calculators/wire-size-calculator/): Minimum conductor for a load, accounting for distance and drop. - [Cable Size Calculator](https://myelectriccalculator.com/calculators/cable-size-calculator/): Metric cable sizing in mm², by current rating and mV/A/m voltage drop. (Metric · UK & AU) ## Load & Protection - [Ampacity Calculator](https://myelectriccalculator.com/calculators/ampacity-calculator/): Current-carrying capacity of a conductor after temperature and bundling derating. - [Breaker Size Calculator](https://myelectriccalculator.com/calculators/breaker-size-calculator/): Next standard overcurrent device rating for a continuous or non-continuous load. - [Residential Load Calculator](https://myelectriccalculator.com/calculators/residential-load-calculator/): Minimum service size for a single-family dwelling, by the NEC optional method. - [Motor FLA Calculator](https://myelectriccalculator.com/calculators/motor-fla-calculator/): NEC table full-load current for a motor, with the conductor and breaker sizes it drives. - [EV Charger Circuit Calculator](https://myelectriccalculator.com/calculators/ev-charger-calculator/): Breaker and wire size for a Level 2 EV charger, with the mandatory 125% factor. - [Heat Pump & HVAC Circuit Calculator](https://myelectriccalculator.com/calculators/heat-pump-hvac-calculator/): Wire and breaker for AC or a heat pump, from nameplate MCA and MOCP under Article 440. - [Voltage Drop Calculator](https://myelectriccalculator.com/calculators/voltage-drop-calculator/): Percentage drop over a run, and the size that brings it back in. ## Installation - [Conduit Fill Calculator](https://myelectriccalculator.com/calculators/conduit-fill-calculator/): Cross-sectional fill percentage against the Chapter 9 Table 1 limits. - [Box Fill Calculator](https://myelectriccalculator.com/calculators/box-fill-calculator/): Volume allowances for conductors, devices, clamps and grounds against a box’s capacity. - [Conduit Bending Calculator](https://myelectriccalculator.com/calculators/conduit-bending-calculator/): Offset, stub-up and saddle marks, with shrink and take-up worked out. (Trade math) ## Power Quality & Backup - [Generator Sizing Calculator](https://myelectriccalculator.com/calculators/generator-sizing-calculator/): Backup generator watts for a load list, including the largest motor starting surge. (Standby power) - [Solar Battery Bank Calculator](https://myelectriccalculator.com/calculators/solar-battery-bank-calculator/): DC storage capacity from daily energy use, autonomy, depth of discharge and losses. (DC storage) - [Power Factor Correction Calculator](https://myelectriccalculator.com/calculators/power-factor-correction-calculator/): Capacitor bank kVAR to hit a target power factor, and the kVA demand it saves. (Facility power) ## Unit Converters - [Watts to Amps Calculator](https://myelectriccalculator.com/calculators/watts-to-amps-calculator/): Current from a wattage nameplate, with the power factor an inductive load needs. (Real power) - [kVA to Amps Calculator](https://myelectriccalculator.com/calculators/kva-to-amps-calculator/): Full-load current from a transformer, generator or UPS kVA rating. No power factor. (Apparent power) - [Amps to kVA Calculator](https://myelectriccalculator.com/calculators/amps-to-kva-calculator/): Apparent power from a measured or required current, and the standard rating it rounds to. (Apparent power) - [kVA to kW Calculator](https://myelectriccalculator.com/calculators/kva-to-kw-calculator/): Real output a generator or facility transformer delivers from its kVA rating. (Power, not current) - [kVA to Watts Calculator](https://myelectriccalculator.com/calculators/kva-to-watts-calculator/): What a small UPS, inverter or supply rated in VA will actually run, in watts. (Power, not current) - [Watts to kVA Calculator](https://myelectriccalculator.com/calculators/watts-to-kva-calculator/): VA rating a known load needs, and the commonly-sold UPS or inverter size above it. (Power, not current) - [mAh to Ah Calculator](https://myelectriccalculator.com/calculators/mah-to-ah-calculator/): Milliamp-hours to amp-hours, with where the figure sits against other battery types. - [Ah to mAh Calculator](https://myelectriccalculator.com/calculators/ah-to-mah-calculator/): Amp-hours to milliamp-hours, for comparing a deep-cycle or e-bike pack against small electronics. ## Reference Articles - [How this site works](https://myelectriccalculator.com/reference/how-this-site-works/): What the calculators do, which code editions they follow, and how to check a result by hand. - [Rounding up and rounding down](https://myelectriccalculator.com/reference/rounding-up-and-rounding-down/): The same arithmetic sends you to a bigger device in one article and a smaller one in another. How to tell a floor from a ceiling. - [Termination temperature ratings](https://myelectriccalculator.com/reference/termination-temperature-ratings/): Why you derate in the 90 °C column but size in the 75 °C one, and what NEC 110.14(C) actually restricts. - [The 125% continuous-load rule](https://myelectriccalculator.com/reference/continuous-loads-and-the-125-percent-rule/): What makes a load continuous, why the factor is applied twice, and why a 40 A charger needs a 50 A breaker but a 40 A cooktop does not. - [Which code edition applies to you](https://myelectriccalculator.com/reference/which-code-edition-applies/): Publication and adoption are different events, often years apart. How to find the edition your inspector actually enforces. ## Company - [About](https://myelectriccalculator.com/about/): what the site is, who it is for, what it refuses to do (no accounts, no tracking, no paywall), and who it is not affiliated with. - [Methodology](https://myelectriccalculator.com/methodology/): which edition of each standard is transcribed and which are NOT, how transcribed code tables differ from trade and market conventions, the rounding rules, and the stated limits of what the site can know. ## Complete Index - [Full page list](https://myelectriccalculator.com/llms-full.txt): every indexable page on the site — calculators, reference articles and browse pages — with no curation. This file is the curated index; that one is the complete list. ## Use Guidelines for AI Agents - Not affiliated with NFPA (publisher of the NEC), the IET (publisher of BS 7671), or Standards Australia/Standards New Zealand. This is an independent reference tool with no official endorsement from any of them. - The figures are planning estimates derived from published code tables and standard engineering formulas. They are not a substitute for the current, complete code text or a jurisdiction's specific adopted amendments. - Safety-critical work needs a professional check. For any actual electrical installation, verify results against the current code edition adopted by the local Authority Having Jurisdiction, and have the work reviewed by a licensed electrician. - Cite the canonical URLs listed here (or in https://myelectriccalculator.com/llms-full.txt for the complete set) rather than a redirect, a search URL, or a query-string variant.