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Head-to-head · Coding Challenge Platforms

AtCoder vs Frontend Mentor

  • Updated Oct 2026
  • Both researched from official sources
  • 2 checks side by side
Higher score AtCoder #5 in Coding Challenge Platforms 8.8/10 Free plan Free plan✓ 1 of 3 features Visit AtCoder
Frontend Mentor #7 in Coding Challenge Platforms 8.6/10 Free plan Free plan✓ 0 of 3 features Try Frontend Mentor

AtCoder leads on 0 checks, Frontend Mentor on 0, and 2 are even. Who comes out ahead on the 2 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreAtCoder · 8.8/10
  • Free planboth
  • Most featuresAtCoder · 1 of 3

AtCoder scores higher on our rubric for coding challenge platforms: 8.8 against 8.6 out of 10; our editors rank them #5 and #7.

AtCoder is the better fit for algorithm and optimization contests. Frontend Mentor is the better fit for frontend project-based challenges.

  • AtCoder fits best

    Algorithm and optimization contests

  • Frontend Mentor fits best

    Frontend project-based challenges

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Side by side

Feature AtCoder 8.8/10 Visit ↗ Frontend Mentor 8.6/10 Visit ↗
At a glance
Editor score 8.8 8.6
Ranking #5 in Coding Challenge Platforms #7 in Coding Challenge Platforms
Best for Algorithm and optimization contests Frontend project-based challenges
Pricing model Free Free plan + paid
Starting price Free plan Free plan
Free plan ✓ ✓
Free trial — —
Deployment Cloud Cloud
Platforms Web Web
Support Tickets, Docs Email, Community, Docs
Built for Solo, Small business, Mid-market, Enterprise Solo, Small business
Features AtCoder 1/3 · Frontend Mentor 0/3
Solution explanations ✓ (best) Not checked yet
Custom challenges Not checked yet Not checked yet
Company assessments Not checked yet Not checked yet
Specs
Primary use Contests Not checked yet
Languages supported C, C++, C#, Java, Python, Rust, Ruby, Go, Kotlin, Swift, JavaScript, TypeScript, PHP, Perl, Lua, Scala, Haskell, OCaml, Nim, Pascal, R, SQL, Prolog, PowerShell, Bash, Fortran, COBOL, Julia, Dart, Elixir, Erlang, F#, D, Crystal, Clojure, Common Lisp, Scheme, Visual Basic, Lean, LLVM IR, Octave, SageMath, Mercury, Pony, Brainfuck, APL, AWK, BASIC, Assembly, Befunge93, Piet Not checked yet
Problem library size 5000 problems Not checked yet
Our review
Pros
  • Free timed algorithm and heuristic contests
  • More than 5,000 archived problems with official editorials
  • Supports many programming languages and rating systems
  • Five difficulty levels cover a range of frontend practice needs.
  • Automated accessibility, HTML, CSS, and JavaScript checks support iteration.
  • GitHub integration, AI reviews, and community feedback support portfolios.
Cons
  • Primarily focused on contests rather than broader coding workflows
  • Web-only access limits platform flexibility
  • Recruitment and assessment services are separate products
  • The learning scope centers on HTML, CSS, and JavaScript.
  • The web-only platform does not provide native desktop or mobile apps.
  • Premium challenges and private solutions require a Pro plan.
Our verdict

AtCoder is a browser-based competitive programming platform for people who want structured algorithm and optimization contests. Operated by AtCoder Inc., it hosts beginner, regular, grand and heuristic formats, with timed submissions…

Read the review →

Frontend Mentor is a web-based coding learning platform for aspiring and practicing frontend developers. It centers on project-based challenges drawn from professional designs or product specifications, letting learners build independently…

Read the review →
  1. AtCoderCoding Challenge Platforms 8.8Free plan
  2. Frontend MentorCoding Challenge Platforms 8.6Free plan

Strengths and trade-offs

  • AtCoder — where it wins

    • Free timed algorithm and heuristic contests
    • More than 5,000 archived problems with official editorials
    • Supports many programming languages and rating systems

    Where it doesn't

    • Primarily focused on contests rather than broader coding workflows
    • Web-only access limits platform flexibility
    • Recruitment and assessment services are separate products

  • Frontend Mentor — where it wins

    • Five difficulty levels cover a range of frontend practice needs.
    • Automated accessibility, HTML, CSS, and JavaScript checks support iteration.
    • GitHub integration, AI reviews, and community feedback support portfolios.

    Where it doesn't

    • The learning scope centers on HTML, CSS, and JavaScript.
    • The web-only platform does not provide native desktop or mobile apps.
    • Premium challenges and private solutions require a Pro plan.
  • AtCoder8.8/10 · Free plan

    A free, contest-focused platform with deep archives, ratings, editorials, and broad language support.

    Visit AtCoderFull verdict →
  • Frontend Mentor8.6/10 · Free plan

    Project-based frontend practice with structured challenges, reviews, and community feedback.

    Try Frontend MentorFull verdict →

More comparisons

All coding challenge platforms comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update