T

TechIdea

Ecosystem

Free Coding Challenges API

The Coding Challenges API offers an extensive library of programming problems ranging from basic data structures to advanced algorithms and system design. It is perfect for technical interview preparation platforms, competitive programming websites, or classroom learning tools. You can filter challenges by category, difficulty, or required programming language.

GEThttps://techidea.online/api/v1/coding-challenges

What is a REST API?

An API (Application Programming Interface) allows two software programs to communicate. A REST API uses standard HTTP requests like GET (to read data), POST (to create data), PUT (to update), and DELETE (to remove).

When you send a request to our https://techidea.online/api/v1/coding-challenges endpoint, our server responds with a JSON (JavaScript Object Notation) array containing data. You can then display this data in your frontend React, Next.js, or mobile applications.

Developer Features

Pagination

Use ?limit=10&page=2

Filtering

Use ?search=keyword

Sorting

Use ?sort=id&order=asc

Code Examples

import { useState, useEffect } from 'react';

function ChallengeList() {
  const [challenges, setChallenges] = useState([]);

  useEffect(() => {
    fetch('https://api.example.com/v1/coding-challenges?difficulty=medium')
      .then(res => res.json())
      .then(data => setChallenges(data.results));
  }, []);

  return (
    <ul>
      {challenges.map(c => <li key={c.id}>{c.title}</li>)}
    </ul>
  );
}

Sample Response

200 OK - application/json
{
  "count": 1500,
  "results": [
    {
      "id": "two-sum",
      "title": "Two Sum",
      "difficulty": "easy",
      "tags": ["array", "hash-table"],
      "description": "Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.",
      "testCases": [
        { "input": "[2,7,11,15], 9", "output": "[0,1]" }
      ]
    }
  ]
}

What to Build (Project Ideas)

Daily Coding Problem Platform

Create a subscription service that emails users a new coding challenge every day.

Implementation Steps

  • 1. Use the API to fetch a pool of challenges categorized by difficulty.
  • 2. Set up a cron job to select one challenge daily based on user preferences.
  • 3. Format the challenge and send it via an email integration service.
  • 4. Provide a web link where users can submit and verify their solutions.

Mock Interview Simulator

An application that pairs users and provides a random challenge for them to solve together.

Implementation Steps

  • 1. Implement WebSockets to create live collaborative coding rooms.
  • 2. Fetch a random medium-level coding challenge from the API.
  • 3. Display the problem statement and test cases on the screen.
  • 4. Allow users to write code, and evaluate it using a code execution engine.

Frequently Asked Questions

Does the API include test cases for the challenges?

Yes, most challenges include sample test cases and hidden test cases for validation.

Can I execute code using this API?

No, this API only provides the challenge content. You will need a separate code execution environment to run and test user submissions.

Continue Learning

Use these resources to deepen your understanding of API integration and build portfolio-worthy projects.

Growth Newsletter

Get practical AI tools, SEO tips, and growth guides weekly.

Join creators, students, and businesses scaling with TechIdea.