If you make your payments online at www.irs.gov/payments, you can pay any amount you like, you don't need to send proof of your calculation. Just make sure to select "2024 form 1040-ES" from the menu as the reason for the payment.
If you want to mail a check, you can print a blank voucher and enter a different amount of your choosing.
https://www.irs.gov/pub/irs-pdf/f1040es.pdf
