I'm about to fix for 10 years at 3.5% (term is 29 years). Mortgage is £144,000. I'm looking to work out what our mortgage will be after 5 and 10 years if we just pay our regular payments but can't seem to find a calculator for that. Would also be good to know what the figure would be after 5 and 10 years if we overpaid bby a certain amount each month (£100 or £200). Can anyone recommend an online calculator for this (or help me with the maths)?