Mainland China Calculator Methodology & Sources

This page brings together the formulas, official sources, editable inputs and review dates used by the mainland China calculators.

Calculation basis

Nationwide rates and statutory formulas use public government, tax, social-security, central-bank or interbank-market sources with effective dates. City, bank and personal inputs remain editable in each calculator.

Calculator methods and sources

• China Individual Income Tax & Annual Bonus Calculator 2026: Comprehensive income is reduced by the ¥60,000 annual basic deduction, entered employee contributions and eligible special additional deductions, then uses the 3%–45% annual progressive table. A separately taxed bonus uses bonus divided by 12 to choose the monthly band, while tax is charged on the full bonus. State Taxation Administration: Individual Income Tax Law
• China Mortgage & Early Repayment Calculator: Equal principal and interest uses the standard fixed-rate amortisation formula. Equal principal repays the same principal each month. A prepayment is allocated in proportion to tranche principal and keeps the planned payment or principal amount, shortening the term. China Foreign Exchange Trade System: June 2026 LPR
• China Home Deed Tax Calculator 2026: First and second homes at or below 140 m² use 1%. Above 140 m², a first home uses 1.5% and a second home uses 2%. Estimated deed tax equals taxable price multiplied by the rate. State Taxation Administration: home deed-tax concessions
• China Vehicle Purchase Tax Calculator 2026: Standard tax is VAT-exclusive taxable price × 10%. In 2026–2027 an eligible new-energy passenger vehicle receives a 50% reduction, but the reduction cannot exceed ¥15,000 per vehicle. State Taxation Administration: 2026 vehicle purchase tax guidance
• China Personal Loan Repayment Calculator: The model divides the entered annual rate by 12 and uses standard fixed-rate amortisation. Extra payments reduce principal; the final instalment is limited to the balance plus that month’s interest. China Foreign Exchange Trade System: LPR reference context
• China Deposit Interest Calculator: Each term earns opening balance × annual rate × months ÷ 12. On renewal, principal and interest become the next term’s opening balance and the rate is assumed unchanged. People’s Bank of China (policy context; use the bank contract rate)
• China Compound Interest & Regular Investment Calculator: The model compounds monthly and places each contribution at month-end. Model growth is ending value less total contributions. Today’s value discounts the future amount using the entered annual inflation rate. People’s Bank of China: general financial context
• China Social Insurance & Housing Fund Calculator: The five social-insurance categories use social-insurance base × entered rate. Housing-fund contributions use housing-fund base × rate. Employee contributions reduce pre-tax pay; employer contributions add to employer cost. Shanghai Human Resources and Social Security Bureau: employer contribution rates
• China Pension Calculator: Base pension = (local calculation base + base × average contribution index) ÷ 2 × contribution years × 1%. Personal-account pension = account balance ÷ the official divisor for retirement age. Human-resources and social-security authority: employee pension formula

Editable inputs

Mortgage defaults use dated LPR and housing provident-fund rates. Social insurance starts with a Shanghai reference. Personal-loan, deposit and compound-growth tools use contract, bank or user-entered scenario inputs. Each tool explains its input basis beside the result.

Review dates

We review the relevant page when a nationwide rule, cited source or Shanghai reference rate changes. Last verified: 25 July 2026. Use the contact page to report a discrepancy.

Using the estimates

Use the results to compare scenarios, then match the final amount to an assessment, payslip, social-insurance record, bank contract or authority determination.