Loans & savings
Early repayment calculator
Compare a regular loan with extra monthly principal payments and an optional lump sum paid immediately.
Your result
Enter your values and calculate. Changing an input clears the previous result.
How this calculation works
Fixed nominal annual interest divided by 12, with equal end-of-month payments. Payment = P × r / (1 − (1 + r)^−n). At zero interest, payment = P / n. Rates stay constant; fees, penalties and variable-rate changes are excluded. The final payment clears the remaining balance. Calculations retain precision internally; displayed and exported amounts are rounded to two decimals. Extra payments reduce principal and shorten the term; the regular installment is retained. The lump sum is paid before the first month's interest. Interest savings compare against the same loan with no extra payments. Prepayment penalties are excluded.
Worked example
With zero interest, a 12,000 loan over 12 months has a 1,000 installment. Paying an extra 1,000 per month clears it in 6 months.