Codechef
HackerRank
AlgoExpert.io
CodeForces
LeetCode
Coderbyte
Interview Cake
Codewars
RepDB
CodeChef is a not-for-profit educational initiative started by Directi more than a decade ago. We started with a dream of seeing an Indian team winning a gold medal at the ACM ICPC World Finals. In its quest for the same, CodeChef has built a self-driven community of the world's best programmers. Today more than 1.3 million competitive programmers from 180+ countries learn from CodeChef. CodeChef has been hosting monthly programming contests regularly for 10 years now. Its platform has assessed 92 million+ code submissions to date, and over 30000 organizations are being impacted by CodeCheffers worldwide. It also organizes SnackDown - one of the world's largest global programming competition whose last edition drew participation from 140+ countries. Since 2017, CodeChef has started providing India's only industry-ready certification in Data Structures and Algorithms, and 1800+ programmers have been certified under the same.
RepDB is a one-time-purchase exercise dataset for developers building fitness and workout apps โ not a subscription, not a rate-limited API. You download the data once and own it: JSON (and SQLite on the higher tier), WebP images, and full EN/DE/ES translations, with no per-request billing and no dependency on our servers staying up.
A free tier includes 400 exercises with flat-style 512ร512 images, attribution-licensed for commercial in-app use. The Starter tier ($199) adds the full catalog in classic white-background style. Standard ($399) adds transparent 1024px images, looping animations, exercise relations (similar/progressions/regressions), workout templates, and embeddings โ exclusive to that tier.
Every exercise includes muscle-group highlighting, equipment/muscle icons, MET values, and safety/goal tags. Compared to GIF- or JPG-based competitor APIs, RepDB images are transparent WebP with no watermarks, so they drop into any app UI without a white box around them.
Codechef RepDBRepDB's answer:
RepDB is sold as a one-time download, not a metered API โ you own the JSON/SQLite data and WebP images outright, with no rate limits, no per-request billing, and no risk of the vendor cutting off access. It's also the only dataset in this space with EN/DE/ES translations, transparent (alpha-channel) images with no watermark, muscle-group highlighting, safety/goal tags, and looping animations on the higher tier.
RepDB's answer:
RepDB grew out of a consumer workout app its creator was building solo. Sourcing exercise images and data meant either paying for a subscription API with usage caps and no caching rights, or producing everything from scratch. The illustrated, multi-language dataset was built for us first, then split out as its own product once it became clear other indie developers had the same problem and preferred to buy the data outright rather than rent it through an API.
RepDB's answer:
Most alternatives are subscription APIs โ you pay monthly, you're capped on requests, and ExerciseDB's terms of use explicitly forbid caching or storing the data at all, so every image render is a live paid API call. RepDB is the opposite: pay once, download the files, self-host with zero ongoing dependency. It's also the only option offering true DE/ES localization and transparent images instead of a white box behind every exercise.
RepDB's answer:
Solo developers and small teams building fitness or workout-tracking apps (iOS, Android, web) who need licensed exercise images and structured exercise data, but don't want to build their own media pipeline or depend on a rate-limited third-party API.
Based on our record, Codechef seems to be more popular. It has been mentiond 7 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Have you heard of codeforces.com, atcoder.jp, codechef.com, etc? Source: over 2 years ago
Leetcode is good to learn basic algorithms because problem statements are usually straightforward. Competitive programming has much wider range of problems. Most popular sites for cp are codeforces.com , atcoder.jp, codechef.com . Source: over 2 years ago
Learn Java with hands-on experience. I personally used codingbat.com a lot, but I've heard good things about codechef.com, which appears to even have a competitive option. Source: over 3 years ago
For practicing algorithms, use any of the freely available websites like https://hackerrank.com https://codechef.com https://projecteuler.net A structured set of practice problems are available at https://www.interviewbit.com/courses/programming/ Avoid https://geeksforgeeks.org because it has a ton of material but very poor quality control. Source: about 4 years ago
These all have sample problems to solve Hackerrank.com edabit.com codewars.com codechef.com and there are tons more. Best of luck to you. I am at about the same level myself. I really like these sites. Source: over 4 years ago
HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.
AlgoExpert.io - A better way to prep for tech interviews
CodeForces - Programming competitions and contests, programming community.
LeetCode - Practice and level up your development skills and prepare for technical interviews.
Coderbyte - Coderbyte is a place built for anyone to practice and perfect their programming skills.
Interview Cake - Free practice programming interview questions. Interview Cake helps you prep for interviews to land offers at companies like Google and Facebook.