Quantum Password Strength API for Developers

Integrate robust password analysis into your application in 5 minutes. Skip building password validation from scratch.

Get Free API Key View Documentation

Fast Integration

Around 5 minutes from API key to production-ready password checking

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Battle-Tested

Production-ready algorithms used by thousands of applications

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Quantum Estimates

Subscription includes quantum resistance estimates (unique!)

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Free Tier

Start with 50 requests/day free - no credit card required (overage disabled without card)

Quick Start Guide To Integrate the Password API

Three simple steps to integrate password checking into your application:

1. Get Your API Key (30 seconds)

Sign up for a free account and get your API key instantly.

Get Free API Key →

2. Quick Domain Setup (2-3 minutes)

For security, verify your domain ownership (one-time setup). Choose your method:

  • DNS TXT Record: Create a TXT record with name _mypasswordchecker and the verification token value from your dashboard (most secure)
  • HTTP File: Download verification file from dashboard and upload to https://yourdomain.com/.well-known/mypasswordchecker-verification.txt (quickest)

DNS Example: For domain aac2.com, add TXT record:
Name: _mypasswordchecker (or _mypasswordchecker.aac2.com if your DNS requires FQDN)
Value: The token from your dashboard (e.g., verify_abc123...)
Some DNS providers use @ for root - check your provider's docs.

3. Make Your First API Call (1 minute)

Send a POST request with your password to analyze:

const response = await fetch('https://mypasswordchecker.com/api/v1/check-password', { method: 'POST', headers: { 'X-API-Key': 'YOUR_API_KEY', 'Content-Type': 'application/json' }, body: JSON.stringify({ password: userPassword }) }); const data = await response.json(); console.log('Strength:', data.strength); // "strong" console.log('Entropy:', data.entropy); // 72.4 bits console.log('Crack time:', data.crack_time.display); // "centuries"

That's it! You're now checking password strength.

API Features

🚀 RESTful JSON API

Simple REST endpoints with JSON request/response. Works with any language or framework.

⚡ <100ms Response

Lightning-fast analysis powered by Cloudflare edge network. Minimal latency.

📊 Entropy Calculation

Accurate entropy measurement showing password unpredictability in bits.

🎯 Pattern Detection

Uses zxcvbn to detect common patterns, dictionary words, and weak structures.

⚛️ Quantum Estimates

Subscription includes quantum resistance analysis (Standard plan and higher).

⏱️ Crack Time Estimates

Real-world crack time estimates based on modern GPU hardware capabilities.

Security & Privacy Practices

🔒 HTTPS Encryption

All API requests transmitted over HTTPS with TLS 1.3 encryption.

🚫 Never Logged or Stored

Passwords are processed in memory only and immediately discarded. We never log or store password values.

💾 In-Memory Processing

Passwords are never written to disk, databases, or cache. Processed entirely in RAM.

🛡️ Domain Verification

Domain verification prevents unauthorized API usage and protects your quota from fraud.

📋 Industry-Standard Security

We follow NIST Cybersecurity Framework best practices and OWASP security guidelines. Hosted on Cloudflare's secure infrastructure with DDoS protection.

📊 Usage Metadata Only

We log only: timestamp, API key ID, endpoint, and response status code. No password data in logs.

✅ Updated: Full Server-Side Processing (Nov 2025)

All 3 API endpoints now return fully calculated data! Our API performs complete server-side analysis:

  • Password Strength: Entropy calculation, pattern detection, crack time estimates, security score (0-4)
  • Quantum Resistance: Grover's algorithm calculations with 3 quantum scenarios (NISQ, Advantage, Supremacy)
  • Phonetic Generation: Cryptographically secure passwords using NATO phonetic alphabet

No client-side libraries required! Just call the API and display results. Worth your subscription!

⚠️ Important: API vs Website Tool

This API processes passwords server-side. When you call our API, passwords are transmitted to our servers for analysis (via HTTPS). All data is processed in memory and immediately discarded - never logged or stored.

If you need 100% client-side processing (password never leaves browser), use our free website tool or view our project overview on GitHub.

Simple, Transparent Pricing

Choose from our flexible API plans. All include the same powerful password analysis.

Plan Price Standard Checks Quantum Estimates Phonetic Gen PQ Keys
Free API $0/mo 50/day - - - Start Free
Standard $12/mo 12,000/mo 100/mo 100/mo - Get Started
Basic Quantum Best Value $29/mo 5,000/mo 1,000/mo 1,000/mo 100/mo Get Started
Standard Quantum $49/mo 25,000/mo 5,000/mo 5,000/mo 1,000/mo Get Started
Large Quantum $99/mo 200,000/mo 50,000/mo 50,000/mo 5,000/mo Get Started
Super Quantum Enterprise $349/mo 800,000/mo 200,000/mo 200,000/mo 20,000/mo Get Started

All plans include: HTTPS encryption • No password logging • In-memory processing • Cancel anytime

View detailed pricing and features →

Common Use Cases

📝 Registration Forms

Validate password strength during user signup. Enforce minimum strength requirements and provide real-time feedback to users.

🔐 Password Policy Enforcement

Ensure corporate password policies are met. Reject weak passwords that don't meet entropy or complexity requirements.

📊 Security Dashboards

Display password strength metrics to users. Show entropy scores, crack time estimates, and quantum resistance levels.

🔄 Password Change Validation

Verify new passwords are stronger than old ones. Prevent users from downgrading to weaker passwords during password changes.

Works With Any Language

Simple REST API works with every programming language and framework

JavaScript
Python
PHP
Ruby
Go
Java

View code examples for all languages →

Ready to Get Started?

Get your free API key and start checking password strength in 5 minutes. No credit card required for free tier.

Get Free API Key →

Free tier: 50 requests/day • No credit card required • Upgrade anytime

Not a Developer?

Just want to test your password strength? Use our free web tool - no API key or registration needed.

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