English interface
Effective annual rate calculator
Estimate an effective annual borrowing cost from net proceeds and equal monthly payments.
ReviewedHigh-impact
Saves this tool's name on this device only (up to 20). No form values.
Only visible result text is included. Form fields are not read. Review sensitive values before sharing.
How to use it
- Enter the amount actually received after known upfront fees.
- Enter the equal monthly payment and number of monthly periods.
- Review the solved monthly rate and effective annual rate against the actual contract cash flows.
Important limitation
Irregular dates, unequal payments, floating rates and charges omitted from net proceeds remain outside scope.
The interactive form is fully localized in English.
Reviewed 2026-09-11; next review 2026-12-11.
IRR from net proceeds and equal instalments has been checked, including numerical edge cases. Irregular dates or payments require the actual schedule.
Sources
Loan Amortization — present value of equal end-of-period paymentsOpenStax, Rice University · opens in a new tabSupports fixed-rate amortization and present value of equal end-of-period payments, not Thai lending rates.Source checked 2026-09-11การเปิดเผยข้อมูลดอกเบี้ยและค่าใช้จ่าย — เอกสารแนบ 5 หน้า 14–15ธนาคารแห่งประเทศไทย · opens in a new tabContext for disclosing assumptions and charges; does not certify this IRR formula as the regulatory EIR for every product or validate a contract.Source checked 2026-09-11Traceable review record
Site changelogReview history
This is the recorded review history available in the repository, not an inferred release history. Dates are added only when evidence is recorded.
- Current review snapshot recorded
IRR from net proceeds and equal instalments has been checked, including numerical edge cases. Irregular dates or payments require the actual schedule.
Method version: review-2026-09-11