I Built a Password Strength Analyzer API with Python + FastAPI 🔐

As a backend developer, I wanted to build something useful, real, and monetizable — not just another tutorial project.

So I built a Password Strength Analyzer API that any developer can integrate into their app in minutes.

What it does

Returns a strength score from 0 (very weak) to 4 (very strong)

Estimates crack time using real-world attack scenarios

Detects if the password is in known breach lists

Returns actionable suggestions to improve security

Analyzes uppercase, lowercase, numbers and symbols

Tech Stack

Python 3.10+

FastAPI — for the REST API

zxcvbn — the same algorithm Dropbox uses

Pydantic — data validation

Render — cloud deployment

Example Request

curl -X POST "https://password-analyzern.onrender.com/analyze" \ -H "Content-Type: application/json" \ -H "X-API-Key: YOUR_API_KEY" \ -d '{"password": "MyP@ssw0rd!"}'

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Example Response

{ "password" : "***********" , "score" : 3 ,…