# Bulk Password Strength Checker — Offline (`comall-agency/password-strength-checker`) Actor

Score passwords in bulk on entropy, character classes, a list of 56 of the most common breached passwords, keyboard sequences and repeated characters, with readable feedback explaining each score. 100% offline, no breach-database lookup, and the password itself is never returned in the output.

- **URL**: https://apify.com/comall-agency/password-strength-checker.md
- **Developed by:** [Comall Agency](https://apify.com/comall-agency) (community)
- **Categories:** Developer tools
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

$3.00 / 1,000 password scoreds

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

Actors are web data automations that power AI and operations. They run on the Apify platform to scrape websites, process data, connect APIs, and automate workflows.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.
Actors are written with capital "A".

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.
The best way to integrate Actors is as follows.

- **AI agents and MCP clients** — the [Apify MCP server](https://docs.apify.com/integrations/mcp.md) at `https://mcp.apify.com` (remote, streamable HTTP, OAuth on first use).
- **Agentic workflows and local Actor development** — [Agent Skills](https://apify.com/.well-known/agent-skills/index.json) with the [Apify CLI](https://docs.apify.com/cli/docs.md): `npm install -g apify-cli`, then `apify login`.
- **JavaScript/TypeScript projects** — the official [JS/TS client](https://docs.apify.com/api/client/js/docs.md): `npm install apify-client`.
- **Python projects** — the official [Python client](https://docs.apify.com/api/client/python/docs.md): `pip install apify-client`.
- **Any other language** — the [REST API](https://docs.apify.com/api/v2.md).

For usage examples, see the [API](#api) section below.

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).

# README

## Password Strength Checker — 100% Offline

Score how strong a password really is, in bulk, without sending it anywhere.
This Actor rates each password on entropy, character variety, known-common
usage and keyboard patterns — not just "does it have a capital and a
symbol".

**100% offline: no external call, no breach-database lookup, no API key.**
And the output never contains the password you sent.

### What it does

Each password receives a score from 0 to 4 (`very_weak`, `weak`, `fair`,
`strong`, `very_strong`), computed from:

- **Entropy** — length multiplied by the log-2 size of the character pool
  actually used (26 lowercase, 26 uppercase, 10 digits, 32 symbols).
- **A common-password list** — 56 embedded entries, the ones that top every
  public breach-corpus analysis (`123456`, `password`, `qwerty`,
  `letmein`…). A match scores 0 immediately, whatever its length or
  character mix.
- **Sequential patterns** — `abcd`, `1234`, `qwer`, `asdf` and their
  reverses.
- **Repeated characters** — three or more identical characters in a row.
- **Character classes used** — lowercase, uppercase, digits, symbols.

It also returns an **estimated crack time**, and returns human-readable
feedback explaining what is holding the score down.

### Use cases

- **Onboarding and signup forms** — score a proposed password server-side
  and tell the user *why* it is weak, not just that it failed a regex.
- **Security audits** — bulk-score a list of passwords from a policy review
  and see how many are genuinely weak rather than merely "non-compliant".
- **Policy design** — test whether your rules actually reject the passwords
  you think they do. Length rules routinely pass `Passw0rd!` and reject a
  strong passphrase.

### Input

```json
{ "passwords": ["password123", "Tr0ub4dor&3", "correct-horse-battery-staple-42"] }
```

### Output (one row per password)

```json
{
  "length": 31,
  "score": 4,
  "score_label": "very_strong",
  "is_common_password": false,
  "has_sequential_pattern": false,
  "has_repeated_chars": false,
  "character_classes": 3,
  "estimated_crack_time": "centuries",
  "feedback": [],
  "checked_at": "2026-08-28T17:00:00.000Z"
}
```

The password itself is deliberately absent from that row.

### Pricing

Pay-per-event: **$0.003 per password scored**, charged once a completed
score is produced.

### Limitations — read this before you buy

- **The crack time is an estimate, not a guarantee.** It assumes an offline
  attack against a fast hash at 10 billion guesses per second. A slow hash
  such as bcrypt or Argon2 makes the real figure far larger; a leaked
  plaintext database makes it irrelevant.
- **The common-password list is short by design** — 56 entries, not a
  multi-megabyte dictionary. It catches the passwords that dominate real
  breach corpora, but a password absent from it is not thereby proven
  unbreached. This Actor does **not** query Have I Been Pwned or any other
  breach service; that is precisely what makes it fully offline.
- Entropy is computed from the character pool used, which **overestimates**
  strength for a word-based password made only of dictionary words.

### Privacy

Passwords are scored in memory and never returned in the output. They do
still travel to the platform as run input and appear in your own run's input
record — so for a production audit, prefer testing candidate policies over
sending live credentials.

### FAQ

**Why does my 16-character password score lower than a shorter one?**
Most often a sequential pattern or a run of repeated characters, both of
which subtract a point. The `feedback` field names the reason.

### Related Actors

Part of the same family of small, single-purpose checkers on this account —
each does one thing, priced per item checked:

- [IBAN Validator & Formatter](https://apify.com/comall-agency/iban-validator-formatter) — ISO 13616 length + mod-97 checksum, fully offline.
- [Card Number Validator (Luhn)](https://apify.com/comall-agency/card-number-validator) — Luhn checksum and card-network detection, output is masked.
- [Barcode Check-Digit Validator](https://apify.com/comall-agency/barcode-checkdigit-validator) — EAN-13, EAN-8 and UPC-A check digits.
- [EU VAT Number Checker](https://apify.com/comall-agency/eu-vat-checker) — official VIES lookup.
- [Email Address Validator](https://apify.com/comall-agency/email-address-validator) — syntax, domain and MX checks.
- [Cron Expression Validator](https://apify.com/comall-agency/cron-expression-tool) — plain-English description and next run times.

# Actor input Schema

## `passwords` (type: `array`):

List of passwords to score. Never stored beyond this run's own dataset — if you don't want a password in your Apify dataset history, don't send it.

## Actor input object example

```json
{
  "passwords": [
    "password123",
    "Tr0ub4dor&3",
    "correct-horse-battery-staple-42"
  ]
}
```

# Actor output Schema

## `results` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "passwords": [
        "password123",
        "Tr0ub4dor&3",
        "correct-horse-battery-staple-42"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("comall-agency/password-strength-checker").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = { "passwords": [
        "password123",
        "Tr0ub4dor&3",
        "correct-horse-battery-staple-42",
    ] }

# Run the Actor and wait for it to finish
run = client.actor("comall-agency/password-strength-checker").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "passwords": [
    "password123",
    "Tr0ub4dor&3",
    "correct-horse-battery-staple-42"
  ]
}' |
apify call comall-agency/password-strength-checker --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,comall-agency/password-strength-checker"
        }
    }
}

```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/ZODYjuaQlThwfmVaF/builds/1vygzOXo1sBL5ItVN/openapi.json