AtCoder vs HackerRank

AtCoder is a free web service for competitive programming contests and practice. Users solve programming problems in Algorithm Contest and Heuristic Contest formats, and can run source code in a browser rather than setting up a local programming environment. Its practice library contains about 5,000 past problems with explanations, and it supports nearly all major programming languages, including C++, Python, Rust, Java, and C#. Beginner Contests take place weekly, Regular Contests about monthly, Grand Contests five to six times a year, and heuristic contests about monthly. Real-time participation in Algorithm or Heuristic contests changes a user's AtCoder rating. AtCoder Jobs lets users apply to companies using their rating for roles including internships and experienced positions. PAST is an online algorithm skills test available in Japanese and English, with problems updated every six months. AtCoder says it has about 200,000 registered users and about 10,000 participants in real-time contests weekly. Its terms limit members to one account and prohibit account sharing, lending, or transfer.

HackerRank helps companies attract, hire, and upskill developers, while also supporting a developer community. Its Screen product offers take-home technical assessments for evaluating applicants in the hiring funnel. Teams can use role-based Certified Assessments or generate a test from an uploaded job description. Screen includes a suspicious-activity model, a proctor, and identity and multiple-face monitoring. HackerRank APIs can automate test administration, interviews, user and team management, candidate data, and question retrieval. Integration categories include ATS, scheduling, talent intelligence, SSO, and productivity tools. The HackerRank for Work platform supports Chrome, Edge, and Firefox on Windows and macOS, plus Safari on macOS; a desktop app is available for Windows and macOS, including Apple Silicon and Intel Macs. HackerRank says its AWS platform complies with ISO 27001 and other listed security standards, and that redundant data centers provide 99.9% service availability. The Starter plan is $165 a month, billed $1,990 billed annually, with one user and 120 attempts per year; additional attempts cost $20. Pro is $375 a month, billed $4,490 billed annually. A free plan and free trial are available.