# Voltformer Sizing Tool

> Preliminary transformer kVA sizing - active power, cos phi, simultaneity and growth reserve. Cable selection is intentionally withheld until site-specific installation, derating, voltage-drop and short-circuit inputs are verified.

Use at https://voltformer.com/sizing-tool or API POST https://voltformer.com/api/v1/tools/calculate-sizing

# Transformer sizing calculator

Estimate transformer kVA from connected load, power factor, diversity and growth reserve.

## Inputs

Connected active load (kW), power factor, diversity, growth reserve (%), voltage and phases.

## Results

Demand kW, apparent kVA, standard rating and preliminary catalog matches.

## Interpretation and limits

Base sizing: kVA = kW × diversity × (1 + reserve/100) / power factor. Site derating may increase the rating. Voltage and phases are required for catalog matching; cable sizing needs a separate site study.

## API tool reference

- [calculateTransformerSizing](https://voltformer.com/agent-api#tool-calculateTransformerSizing)

[Open tool](https://voltformer.com/sizing-tool)