See if this Intuit article helps.   It shows the marginal rates for 2025 (for returns filed in 2026).   That means if you move into a higher bracket, the increased percentage (the increased tax rate) applies only to the amount of income that exceeds the amount of the preceding bracket.  Scroll down about half page to get to the 2025 brackets.

Intuit Tax Tips:  Tax Brackets and Tax Rates

https://turbotax.intuit.com/tax-tips/irs-tax-return/current-federal-tax-rate-schedules/L7Bjs1EAD