# Unit Converter - List Units by Measure

> Unit Converter - List Units by Measure is a paid API for AI agents from unit.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Lists all available unit types and conversion options for a given measurement category (e.g. length, mass, temperature).

## Facts

- Endpoint: POST https://unit.openverbs.com/v1/list
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/unit-converter-list-units-by-measure-74658b34
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_JlsOLEu8N_fFHFuNKmUAf

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability unit-converter-list-units-by-measure-74658b34 -d '<json body>'
```

Example prompt: What units are available for converting mass measurements? I want to see everything supported under the mass category.

## When to prefer this

Use this endpoint when you need to discover what units are available before performing a conversion, or when building a UI that lets users select units dynamically. Ideal for populating dropdowns, validating user input unit names, or checking if a specific unit type is supported within a given measurement category.

## Known failure modes

- Invalid measure enum value returns an error — must be one of the 23 supported categories
- Empty or malformed body may return a validation error
- Network timeout for slow connections
- Payment failure if USDC balance is insufficient for the $0.002 per-call fee

## How this service works

List the supported units and their metadata (abbreviation, measure, system, singular/plural names), optionally filtered to a single measure — a discovery endpoint for choosing valid `from`/`to` values.

## Output

Returns a list of all supported units within the specified measurement category (e.g. all length units: meters, feet, inches, etc.), or all units across all categories if no measure filter is provided.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "measure": {
       "type": "string",
       "enum": [
        "length",
        "area",
        "mass",
        "volume",
        "each",
        "temperature",
        "time",
        "digital",
        "partsPer",
        "speed",
        "pace",
        "pressure",
        "current",
        "voltage",
        "power",
        "reactivePower",
        "apparentPower",
        "energy",
        "reactiveEnergy",
        "volumeFlowRate",
        "illuminance",
        "frequency",
        "angle"
       ],
       "description": "Restrict to one measure, one of length, area, mass, volume, each, temperature, time, digital, partsPer, speed, pace, pressure, current, voltage, power, reactivePower, apparentPower, energy, reactiveEnergy, volumeFlowRate, illuminance, frequency, angle."
      }
     },
     "required": [],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/unit-converter-list-units-by-measure-74658b34/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from unit.openverbs.com](https://www.zero.xyz/host/unit.openverbs.com/llms.txt)