Documentation sections

Power Amplifier Efficiency Calculator (PAE & Drain Efficiency)

POSThttps://rftools.io/api/py/v1/calculate

Slug power-amplifier-efficiency. Calculate RF power amplifier PAE, drain efficiency, gain, and heat dissipation from Pout, Pin, and DC bias. Essential for PA design. Free, instant results.

Inputs

Send every one of these in inputs, in the units shown. Most are required: a call without one is refused (400) and costs nothing; one the calculator can do without takes the default shown. An input outside its range is still computed and flagged in the provenance.

Inputs of power-amplifier-efficiency
Name	Unit	Range	Default	Description
outputPowernumber	dBm	any	30	RF output power in dBm (30 dBm = 1 W)
inputPowernumber	dBm	any	0	RF input drive power in dBm
dcVoltagenumber	V	at least 0.1	5	DC bias supply voltage
dcCurrentnumber	mA	at least 0.1	500	DC current draw from supply in mA
targetPaenumber	%	0 … 100	40	The power-added efficiency the amplifier must reach. The status fails below 20 %.

Outputs

Returned in values, by key. A value that is unbounded or undefined is null.

Outputs of power-amplifier-efficiency
Field	Unit	Description
gain	dB	Gain
dcPower	mW	DC Power Consumed
paeheadline	%	Power-Added Efficiency
drainEfficiency	%	Drain Efficiency
dissipatedPower	mW	Dissipated Power (Heat)

Calling it

Calculate: one call, the request and response in full, and its errors.
Batch: this calculator with others, or a sweep, in one request.
Solve for a target: the value of one input that brings an output to a target.

curl -X POST https://rftools.io/api/py/v1/calculate \
  -H "X-API-Key: $RFTOOLS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "power-amplifier-efficiency",
    "inputs": {
      "outputPower": 30,
      "inputPower": 0,
      "dcVoltage": 5,
      "dcCurrent": 500,
      "targetPae": 40
    }
  }'

import rftools

client = rftools.Client()  # reads RFTOOLS_API_KEY, or the key `rftools login` saved

result = client.calculate("power-amplifier-efficiency", {
    "outputPower": 30,
    "inputPower": 0,
    "dcVoltage": 5,
    "dcCurrent": 500,
    "targetPae": 40,
})
print(result.values)
print(result.warnings, result.provenance.formula_ref)

const response = await fetch("https://rftools.io/api/py/v1/calculate", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.RFTOOLS_API_KEY,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "slug": "power-amplifier-efficiency",
    "inputs": {
      "outputPower": 30,
      "inputPower": 0,
      "dcVoltage": 5,
      "dcCurrent": 500,
      "targetPae": 40
    }
  }),
});
console.log(response.status, await response.json());

package main

import (
	"bytes"
	"fmt"
	"io"
	"net/http"
	"os"
)

func main() {
	body := []byte(`{
	  "slug": "power-amplifier-efficiency",
	  "inputs": {
	    "outputPower": 30,
	    "inputPower": 0,
	    "dcVoltage": 5,
	    "dcCurrent": 500,
	    "targetPae": 40
	  }
	}`)
	req, err := http.NewRequest("POST", "https://rftools.io/api/py/v1/calculate", bytes.NewReader(body))
	if err != nil {
		panic(err)
	}
	req.Header.Set("X-API-Key", os.Getenv("RFTOOLS_API_KEY"))
	req.Header.Set("Content-Type", "application/json")
	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()
	out, _ := io.ReadAll(res.Body)
	fmt.Println(res.Status, string(out))
}

application/json

{
  "slug": "power-amplifier-efficiency",
  "values": {
    "gain": 30,
    "dcPower": 2500,
    "pae": 39.96,
    "drainEfficiency": 40,
    "dissipatedPower": 1500
  },
  "warnings": [],
  "errors": [],
  "provenance": {
    "method": "calculator:power-amplifier-efficiency",
    "version": "api@3f2c1a9b04de",
    "formulaRef": "RF Power Amplifiers for Wireless Communications, 2nd ed., Steve C. Cripps (2006), Chapter 2 — Efficiency definitions",
    "assumptions": [],
    "validRange": {
      "status": "inside",
      "bounds": {
        "outputPower": {
          "min": null,
          "max": null,
          "unit": "dBm"
        },
        "inputPower": {
          "min": null,
          "max": null,
          "unit": "dBm"
        },
        "dcVoltage": {
          "min": 0.1,
          "max": null,
          "unit": "V"
        },
        "dcCurrent": {
          "min": 0.1,
          "max": null,
          "unit": "mA"
        },
        "targetPae": {
          "min": 0,
          "max": 100,
          "unit": "%"
        }
      },
      "outside": [],
      "model": null
    },
    "computedAt": "2026-09-24T14:05:11.003Z",
    "inputs": {
      "outputPower": 30,
      "inputPower": 0,
      "dcVoltage": 5,
      "dcCurrent": 500,
      "targetPae": 40
    },
    "seed": null,
    "elapsedSeconds": 0.003
  }
}

{
  "detail": [
    {
      "type": "float_parsing",
      "loc": [
        "body",
        "inputs",
        "outputPower"
      ],
      "msg": "Input should be a valid number, unable to parse string as a number",
      "input": "abc"
    }
  ]
}

An input sent as text. Nothing was counted.

{
  "detail": "More than 120 requests in 60 seconds from this address.",
  "errorKind": "rate_limited",
  "limit": 120,
  "windowSeconds": 60,
  "upgradeUrl": "https://rftools.io/pricing/"
}

Too many requests in a minute, with Retry-After.

Same inputs on the calculator pagePower Amplifier Efficiency Calculator (PAE & Drain Efficiency), at these values