Codeforces 1v1 Duel — Challenge, Compete, and Climb the Leaderboard!
Hey everyone!
I’ve built something fun for all competitive programmers — a 1v1 Codeforces Duel platform where you can battle other coders in real time! Try it here: https://cfduel.vercel.app
What is Codeforces Duel? A place where you can duel with other users on real Codeforces problems. You can either:
Find a new opponent using the matchmaking system or Create a Duel ID and invite your friend
Key Features
Smart Matchmaking — automatically pairs you with players of similar rating
Custom Problem Filters — choose by tags, rating range, or even year of release
Live Timer — tracks the match in real time
Draw & Give Up options — just like real competitive battles
Leaderboard — track your duel rating and compete globally
Live chat — you can chat with opponent during match
Tech Behind the Platform Built using: React Node.js + WebSockets Codeforces API integration
Try it here: https://cfduel.vercel.app
Watch Demo here https://www.youtube.com/watch?v=eu9zR9WDju0
Whether you want to warm up before a contest or challenge your friends for fun, Codeforces Duel makes every problem a battle worth fighting.








Seems amazing! Great job! However I could not joined the match, since there are too little number of users. I guess it would be popular soon.
yeah I hope so. if you got any friend you can create room and share id to your friend
Oh, that's awesome. I will try it
duel me
Seems good, however I think there would be the problem of cheating or getting a problem you've previously done before.
yeah previously solved problem issue exist will fix it by tmrw if any one has idea please share it on how to handle efficently? In future will fix cheating issue's also suggest me if you any ideas about that
just solved the problem you wont get an previously solved problem
omg im 4th now
How was the website?
It was amazing, but I believe it will be better if there are more people using it
This project is fantastic!. I love the smart matchmaking and custom filters that allow users to tailor their experience. If only 1v1 matches could be as thrilling as group challenges or tournaments involving multiple players. This is undoubtedly the best website ever! It's perfect for competitive programming fans who want to improve their skills.
Thank you, will bring more features in future
omg its cool actually
I also suggest you add something like "quick match", in order to connect to someone who chose other parameters (difficulty, time...)
That's Awesome bro!!
Thank you man. I think I should check wether both users solved it before or not implementing it will be fixed soon.
That's Great , best of luck!!
Appreciable, nice UI.
Thanks
Just reading the introduction makes me think this is a genius idea! But I noticed that the website seems to be inaccessible in my region unless I use a VPN, and unfortunately, my VPN stopped working a few days ago. This has to be the unluckiest thing that’s happened to me this month :(
oh which country are you from , I will figure it out why is it happening
Don't worry, as long as you click into my homepage and see my nationality, you will understand that this is not an issue with your website.
Got it man
Hi, I just want to say amazing app, I think it would improve cf 1v1's overall, but I have a massive problem: - It gives us problems that we've done before, I think this is highly unfair, especially if you still remember the solutions
But, overall, great job! keep it up!
yeah true will fix it soon
Thank you for your effort <3. I think it will be fun if you add team vs team mode.
thanks ,sure will add it soon
I just added team vs team , you can check it out it's live now
Thank you <3
Why don't you also add "login with Codeforces" feature, since now it supports OAuth.
Thanks , I didnt knew this exists will add soon
There is already a similar site existing (and even with stronger abilities) https://algorithm-duels.online/home, although it's in Chinese.
oh tell me what all features that have better than mine? I cant use it it's in chinese will try with translator?
btw your website is also excellent. Keep it up and hope it will support more features in the future.
thanks , will bring this features soon
I think https://algorithm-duels.online is a good website too
pretty cool, i hope my friends wants join to duel me up!
thanks , I hope so .
nobody wants to play with me, but the site idea is great)
Thanks as users grows , you get matched with someone soon . Meanwhile you can duel with friend, create a duel and share the code
Appreciated... going to use with my friends.
Can you provide the source code? I want to see the tech behind it.
as of now its private I will share you soon
Just tried it, its really cool. Keep it up Sudheer!
Thank you
Cool app.
Thanks man
Great job! I've been using Codingame until now, but it only has minor issues. This is amazing!
Thank you , what issues it has please tell me will fix it soon
Great job, it is a fun way to do cp
great project. do you use polling to fetch submission status during duels?
Yes i used polling
Found it very usefull.
Completed my 20th duel today!
Thanks , good to hear this
WATCH DEMO!!!
Amazing platform !
But it suffers from a lack of users :( I hope it gets popular soon!
Thanks , I hope it get more users
I just checked the Login/Sign Up page and saw that it accepts either a Mail ID + Password, or Google OAuth. Would it be possible to add a direct Single Sign-On (SSO) login using CodeForces, if its API provides this?
What is the maximum number of users it can support at a particular time?
why there is no option for multiple problems?