Let's see, Magnus at 9 year's old is probably 1400 to 1600.
Estimate my rating based on 'play magnus' app

Well 1 game doesn't mean much since the 9 year old Magnus makes quite a few mistakes. If you can consistently (5-10 wins in a row) beat him with no takebacks, you'd be around 14-1500.
Magnus Carlsen at 9 years flat was rating 904, so I'd say the Play Magnus app at 9-10 years is around 1200 given his fast improvements.

I played against the app back in highschool (was solid club player) and after about 12 years old it's a no-go unless you willing to really analyze (which I didn't since screen strained my eyes).

the 9 year old is playing above 1400 IMO. don't forget either that if you play the month by month of magnus 9, the skill level jumps a bit til age 10. when magnus played his first big tourney he was rated just over 2000. would it be safer to say that the 9 year old and 0 months is about an 1800?

@OP, this is very promising. However, to get a good estimate of your playing strength, you need to play OTB

Update: I just played 10 year old Magnus which ended in a draw. I think I'm about equal with the 10 year old setting on the app.

Unfortunately, the OP's account has been closed, so we won't know if he was really talented or just bragging/cheating...

Unfortunately, the OP's account has been closed, so we won't know if he was really talented or just bragging/cheating...
Magnus got angry and had his account closed.
the 9 year old is playing above 1400 IMO. don't forget either that if you play the month by month of magnus 9, the skill level jumps a bit til age 10. when magnus played his first big tourney he was rated just over 2000. would it be safer to say that the 9 year old and 0 months is about an 1800?
I think that 9yrs old Magnus is 1200, and he reaches 1500 in 10yrs old, since I could beat 9yrs old magnus consistently, but not 10yrs old.

at 10 yrs old Magnus was a titled player. I've played the app and 9 yrs old is certainly stronger than 1200.

The app punishes you for tactical mistakes, but fails in more positional lines. Had a win against 14 year old Magnus in a Maroczy Bind position.

you have played chess for just a month and beat magnus 9? which engine did you use to aid the victory?

I managed to beat magnus at 9 Years and 7 month(1 to 6 as well) and drawed against him at 9 years and 8 month so I guess 1600.
I was close to beat him at 8 month but fell for a stalemate trap
edit: just beat him at 8 and 9 month now I will attempt 10 month.
I have beat him at every month as 8 year
I started playing chess about a month ago so I have no idea what my rating would be. I just beat 9 year old magnus. How good is 9 year old setting on the play magnus app?