Codeforces vs HackerRank

Codeforces is a programming-contest community and platform where regular contests give participants a way to solve problems and earn skill ratings. The site says it organizes approximately six contests each month, with free participation open to everybody. In contests following Codeforces rules, participants gain points for solving problems quickly and can test other contestants’ solutions through hacks. Ratings use a modified Elo system, and contestants are split into two divisions. The online judge checks submissions against prepared tests and tests suggested through hacks, then returns a verdict. Past contests are available for practice, while the site says learning content and training features are in development. Codeforces also offers an API that returns some data as machine-readable JSON over HTTP. Public data can be requested anonymously; private user data requires an API key. API requests are limited to one every two seconds, and faster calls receive a call-limit error. The service is free and available on web and through an API.

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.