Docs/APIs/Unit Converter

Unit Converter

Convert units

OperationalCredits 1 per callp50 814msData ConversionStar

Overview

Unit Converter works by using formulas to convert units from one to another. Using a well defined set of units, it returns the converted value to the desired unit.

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

GEThttps://api.apiverve.com/v1/unitconverter
curl "https://api.apiverve.com/v1/unitconverter?value=100&from=lb&to=kg" \
  -H "x-api-key: your_api_key_here"
const res = await fetch('https://api.apiverve.com/v1/unitconverter?value=100&from=lb&to=kg', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);
import requests

res = requests.get(
    "https://api.apiverve.com/v1/unitconverter?value=100&from=lb&to=kg",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])
package main

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

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/unitconverter?value=100&from=lb&to=kg", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

ParameterTypeDescription
valueRequirednumberThe value to convert
fromRequiredstringThe unit to convert from
toRequiredstringThe unit to convert to

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

Sample response
{
  "status": "ok",
  "error": null,
  "data": {
    "result": {
      "result": 45.36,
      "from": "100 lb",
      "to": "kg"
    },
    "unitDefinitions": {
      "from": {
        "abbr": "lb",
        "measure": "mass",
        "system": "imperial",
        "singular": "Pound",
        "plural": "Pounds"
      },
      "to": {
        "abbr": "kg",
        "measure": "mass",
        "system": "metric",
        "singular": "Kilogram",
        "plural": "Kilograms"
      }
    }
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

FieldTypeExampleDescription
resultobject{...}
resultnumber45.36Converted numeric value in target units
fromstring"100 lb"Original value with source unit abbreviation
tostring"kg"Target unit abbreviation for conversion
unitDefinitionsobject{...}
fromobject{...}
abbrPremiumstring"lb"Source unit abbreviation code
measurePremiumstring"mass"Physical quantity being measured from
systemPremiumstring"imperial"Measurement system of source unit
singularPremiumstring"Pound"Singular name of source unit
pluralPremiumstring"Pounds"Plural name of source unit
toobject{...}
abbrPremiumstring"kg"Target unit abbreviation code
measurePremiumstring"mass"Physical quantity being measured to
systemPremiumstring"metric"Measurement system of target unit
singularPremiumstring"Kilogram"Singular name of target unit
pluralPremiumstring"Kilograms"Plural name of target unit

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

StatusMeaningWhat to do
400Input was rejectedRead error; it names the parameter.
401Key missing or invalidCheck the header name and the key value.
403Key valid, but not permittedA key restriction or IP allow-list; see key scoping.
429Rate limited, or out of creditsRead error to tell them apart; see rate limits.

Use cases

Measurement Converters
Convert measurements such as weight, length, area, temperature, and more by using the Unit Converter API. Use the API to convert units between different systems
Unit Standardization
Standardize units across different systems by using the Unit Converter API. Convert units to a common standard for consistency and compatibility
Unit Calculation
Perform unit calculations by using the Unit Converter API to convert units in mathematical operations. Use the API to simplify unit conversions in calculations

Other ways to use Unit Converter

Set up Unit Converter on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKitReference →
Use it in Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.VerveSheetsReference →
Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContextReference →

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