# 402utils Unit Converter

> 402utils Unit Converter is a paid API for AI agents from 402utils.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Converts a numeric value between units of the same physical dimension (length, mass, volume, temperature, area, speed, data, energy, pressure, time, angle) using exact SI constants, or between ISO 4217 currencies at ECB reference rates.

## Facts

- Endpoint: POST https://402utils.com/v1/unit-convert
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/402utils-unit-converter-57dab6bf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Sjmhkcofy0Q8f2IKbowK3

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 402utils-unit-converter-57dab6bf -d '<json body>'
```

Example prompt: Convert 26.2 miles to kilometers for me — I need the exact number based on SI constants.

## When to prefer this

Use this endpoint when you need deterministic, exact unit conversions using NIST SI constants rather than relying on an LLM's approximation. Ideal for scientific, engineering, or data-processing pipelines where precision matters. Also useful for quick ECB-rate currency conversions when exact pricing is not required. Prefer this over general-purpose LLM math for any physical dimension conversion where correctness is critical.

## Known failure modes

- Unknown source or target unit returns 400 with a unit suggestion
- Mismatched dimensions (e.g. kg to meters) returns 400 error
- Missing required fields (value, from, to) returns 400 validation error
- Currency category requested but non-ISO-4217 codes supplied returns 400
- Network or service unavailability returns 5xx error

## How this service works

Convert a value between units in the same physical dimension: length, mass, volume, temperature, area, speed, data, energy, pressure, time, angle. Factors are exact SI constants (NIST SP 811) — deterministic, unlike an LLM's guess. Pass ?category=currency to convert ISO 4217 amounts at ECB reference rates instead (informational, not for pricing). Unknown units → 400 with a suggestion.

## Output

Returns the converted numeric value in the target unit, computed using exact NIST SP 811 SI constants (deterministic, not estimated). For currency conversions, returns the converted amount at ECB reference rates. Unknown or mismatched units return a 400 error with a suggested correction.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "to": {
   "type": "string",
   "description": "Target unit (same dimension as `from`)."
  },
  "from": {
   "type": "string",
   "description": "Source unit (e.g. mile, kg, celsius) or ISO 4217 code for currency."
  },
  "value": {
   "type": "number",
   "description": "The amount to convert."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/402utils-unit-converter-57dab6bf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 402utils.com](https://www.zero.xyz/host/402utils.com/llms.txt)