# Vextorium Password Strength Estimator (zxcvbn)

> Vextorium Password Strength Estimator (zxcvbn) is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-16).

Estimates password strength using Dropbox's zxcvbn algorithm, returning a score 0–4, crack time estimates for online/offline attacks, weak patterns detected, and improvement tips — evaluated in memory, never stored.

## Facts

- Endpoint: POST https://api.vextorium.com/fuerza-contrasena-pago?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vextorium-password-strength-estimator-zxcvbn-1eaffc46
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_S2L11-NHthijlL43r9VS5

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 vextorium-password-strength-estimator-zxcvbn-1eaffc46 -d '<json body>'
```

Example prompt: How strong is the password 'Sunfl0wer2024!'? Give me the zxcvbn score, estimated crack time for online and offline attacks, any weak patterns found, and suggestions to make it stronger.

## When to prefer this

Choose this endpoint when you need a fast, privacy-respecting, in-memory password strength analysis powered by Dropbox's well-established zxcvbn algorithm, especially when you want structured crack-time estimates across multiple attack scenarios and actionable tips — without risk of the password being logged or stored server-side.

## Known failure modes

- Missing 'contrasena' field in request body returns validation error
- Empty or null password string may return a score of 0 with no patterns
- Network timeout if the service is temporarily unavailable
- Invalid bodyType value causes request rejection

## How this service works

Estimate password strength with Dropbox's zxcvbn: score 0-4, estimated guesses and crack time for online and offline attacks, weak patterns found (dictionary, dates, sequences...) and tips. Evaluated in memory, never stored or logged.

## Output

Returns a JSON object with: a numeric score (0–4), a human-readable strength level (e.g. 'muy débil'), estimated number of guesses, crack times for four attack scenarios (online unlimited, online rate-limited, slow offline hash, fast offline hash), an array of detected weak pattern types (e.g. 'dictionary', 'date', 'sequence'), an array of improvement tips, an optional warning message, and a privacy note confirming the password is never stored.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "contrasena": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "nota": "La contraseña se analiza en memoria y no se almacena. Mejor aún: evalúala en local y no la envíes a ningún servicio.",
  "aviso": "This is a very common password.",
  "nivel": "muy débil",
  "consejos": [
   "Add another word or two. Uncommon words are better."
  ],
  "longitud": 11,
  "puntuacion": 0,
  "patrones_debiles": [
   "dictionary"
  ],
  "tiempo_descifrado": {
   "online": "60 seconds",
   "online_limitado": "6 hours",
   "offline_hash_lento": "less than a second",
   "offline_hash_rapido": "less than a second"
  },
  "intentos_estimados": "596"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vextorium-password-strength-estimator-zxcvbn-1eaffc46/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)