UPD: Thank you all for 300+ downloads in just a week! I've shipped an update with new features like analytics. Details are in this post!
TLDR: Create custom contests instantly to efficiently train! Download on the Chrome Web Store
Train Specific Skills & Improve Rating
Frustrated when problems in virtual contests jump from doable to impossible? Want to train speed or problem solving specifically? The CF Custom Contests extension makes this effortless!
Key Features
This extension elevates your training experience by providing the following features
- Contest Settings: Choose problem count & ratings and contest length. Short contest + easier problems for speed drills OR longer contest + harder problems for problem solving practice
- Contest: Solve customized problems in the familiar CF contest format. One-click rerolls if you get stuck
- Contest Results: Analyze your performance with detailed results. Problem solve times tracked in real-time
Preview the UI

How To Get Started
- Add to Chrome or Add to Firefox
- Navigate to the new “Custom Contest” tab next to the “Contests” tab
- Tailor the settings to your needs and start solving!
Practice smarter with CF Custom Contests and hit your next rating milestone! Get started now!
Have any suggestions or thoughts? Drop it below and I’ll respond :)








Amazing!!
Thank you so much :)
Installed. Better than anything else I've seen.
Thank you for your kind words :)
It's almost the replica of ThemeCp!!
Please add the preview UI of performance analyze and contest history too. I'm curious about that part how'd the calculations of performance and rating changes goes.
Well done, Bro
Thanks, glad you like it!
Thanks a lot, bro. This is amazing.
Really appreciate your support! :)
This is actually very useful, thanks a lot for this man!
Really appreciate it! :)
Uh, hey, I think I found a small bug; If you choose to have more than three problems in the contest, and you decide to choose the rating for the fourth problem or the problems after it, the drop down by default opens from problem 3. Please fix this soon.
I couldn't reproduce the issue for some reason :/. Is there anything else you are doing other than adding a new problem and trying to choose its rating?
Ah yup, when I add two three new problems (making 6 or more in total), and then I scroll a bit to choose the rating for the latter problems (6th or later), then the drop down is dropped in "not the correct way", I guess you can see it here.
Image Here
Oh yeah, I see what you're saying. Not sure why that bug happens since selecting a value in the dropdown still changes the correct rating, but I'll fix it in the next update. Thank you for reporting this! :)
Amazing! It make us create a contest easily in custom.
I think perhaps a function could be added: selecting the participants of this contest. In this way, it is possible to quickly determine whether the randomly selected topic has already been submitted or approved by them. I think this is a very great invention for those who want to organize trainings for some teams, because when organizing trainings, it is necessary to ensure that the participants have not done these problems as much as possible.
cool but feels way too themeCP like, maybe try to add your own twist?
AvDev The extension is super Brilliant! But I have a device:
When the next time you update this extension, can you add a filter that we can choose the tag(s) we want? If you can, that's perfect!
Sorry for my poor English. :)
Anyway, it's the best codeforces extension I've ever seen!!!
Warning to future generations: If you started a contest using this extension,
Don't refresh the page!
Don't refresh the page!
Don't refresh the page!
Or there's nothing left. XD
Yep, I’ll add a tag filter! Thanks :)
When? qwq
The most recent version of the extension has the tag filtering feature, so could you check the extension's version you have and update it if necessary?
Ok Thank you very much
This is great , I've been trying my hands on it lately and its quite a nice approach for practicing. Could you just make a fix so that it gives like open contest based problems, like excluding the language specific contests like Kotlin Heroes or Microsoft #Q's and all
I get questions like this during a contest https://codeforces.me/problemset/problem/1001/D
Is the firefox extension available now?