What this app does
Plots your entire rating history from your very first contest and overlays a fitted regression curve (linear, quadratic, or cubic) to best approximate your rating trend
Projected curve fit into your rating chart
Actual contest rating changes in all the contests a user has participated in so far
Predicts your future rating month-by-month until December 2025. Future Rating Predictions (Monthly till Dec 2025)
Approach
1. Fetches a user's entire contest history : Codeforces RatingChange API
Each contest entry includes:
contestId: Unique ID of the contest
contestName: Name of the contest
handle: User's Codeforces handle
newRating: Rating after the contest
ratingUpdateTimeSeconds: UNIX timestamp (converted to a readable date)
2. Machine Learning technique — Polynomial Regression : Fits a smooth curve through a user's rating history using polynomial regression.
I tried linear regression, and polynomial regression with degrees 2 and 3 but since most people participated in less than 100 contests, polynomial regression (with degrees 2 and 3) caused overfitting and showed absurd results but it works fine for some users who participated in a large number of contests.
I tried to improve the balance in the dataset before training by sampling some data points for some users with very less number of contests but i suggest most users to use the Linear regression approach (Polynomial Regression with degree 1) in order to obtain smooth and more accurate results but I have given the option to view the results produced by the higher degree polynomials as well in the dropdown in the bottom of the page.
You can access it from here : Codeforces Future rating Predictor
NOTE : Since I used the free-tier of Render to deploy the backend, it will spin down to sleep mode in case of prolonged inactivity and in such cases it would take slightly longer time to return results (3-4 mins), otherwise it would return results instantly in few seconds.
Disclaimer
These predictions are NOT 100% accurate. They are generated using your past contest ratings only. The model does not account for upcoming contest performance, competition difficulty, relative ranking, or rating inflation. Also, the more contests a user has participated in, the better the prediction will be.
Looking forward for your feedback, Thank you!
