RRSP is based on 18% of your previous year's income up to $30,780 for 2023 (this amount adjusted each year)
https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/rrsps-related-plans/contributing-a-rrsp-prpp/contributions-affect-your-rrsp-prpp-deduction-limit.html
How is your RRSP deduction limit determined
The Canada Revenue Agency generally calculates your RRSP deduction limit as follows:
your unused RRSP deduction room at the end of the preceding year
Plus
The lesser of the two following items:
18% of your earned income in the previous year
the annual RRSP limit (for 2023, the annual limit is $30,780)
That exceeds one of the following items:
your pension adjustment (PA)
your prescribed amount for connected persons
Plus
your pension adjustment reversal (PAR)
Minus
your net past service pension adjustment (PSPA)
If you want to calculate your RRSP deduction limit yourself, see chart 3 of Guide T4040, RRSPs and Other Registered Plans for Retirement.
https://www.canada.ca/en/revenue-agency/services/forms-publications/publications/t4040/rrsps-other-registered-plans-retirement.html