# Password Strength Estimator

> Password Strength Estimator is a paid API for AI agents from password.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Estimates the strength of a password by returning a score, guess count, crack-time estimates, and actionable feedback — without storing the password.

## Facts

- Endpoint: POST https://password.openverbs.com/v1/strength
- 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/password-strength-estimator-56145bfa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nwok0ly5FmgQYPmg7QzFQ

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 password-strength-estimator-56145bfa -d '<json body>'
```

Example prompt: Can you check how strong the password 'Tr0ub4dor&3' is, and factor in that my username is 'john' so it penalizes that if it shows up?

## When to prefer this

Use this endpoint when you need real-time, per-password strength analysis with human-readable feedback and crack-time estimates — ideal for signup flows, password policy enforcement, or user-facing coaching. Prefer it over generic regex checks when you need nuanced scoring that accounts for user-specific context terms like names or app names.

## Known failure modes

- Empty or missing 'password' field returns a validation error
- Password exceeding 512 characters is rejected
- Malformed request body (wrong bodyType or missing required fields) returns a 400-level error
- If context terms (userInputs) contain more than 50 items or items over 128 characters, the request may be rejected

## How this service works

Estimate password strength: score, guesses, crack-time and feedback. Never stored.

## Output

Returns a numeric strength score (typically 0–4), an estimated number of guesses required to crack the password, human-readable crack-time estimates (e.g. 'centuries', '3 hours'), and structured feedback including warning messages and suggestions for improvement. The password is never logged or stored.

## 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": {
      "password": {
       "type": "string",
       "minLength": 1,
       "maxLength": 512,
       "description": "The password to evaluate. Not logged or stored."
      },
      "userInputs": {
       "type": "array",
       "items": {
        "type": "string",
        "maxLength": 128
       },
       "maxItems": 50,
       "description": "Context terms (name, email, app) to penalize if present."
      }
     },
     "required": [
      "password"
     ],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/password-strength-estimator-56145bfa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from password.openverbs.com](https://www.zero.xyz/host/password.openverbs.com/llms.txt)