Deterministic Japan statutory calculations with cited primary sources: net pay, social insurance, income walls, bonus, consumption tax, business days, overtime, retirement tax, payslip audit and crypto tax. x402 (USDC on Base), no API key; failed calls are never charged.
Scored across 16 tools
Each tool targets a clearly distinct calculation or lookup domain, and the descriptions explicitly cross-reference alternatives (e.g. jp_payroll_net vs jp_payroll_suite vs jp_social_insurance vs jp_payslip_audit). The three get_* meta tools are also clearly separated from the paid statutory calculators.
All names use snake_case consistently, with paid domain tools sharing the jp_ prefix and meta tools using get_. The only minor inconsistency is that meta tools are verb-first while domain calculators are noun-phrase based, but the pattern remains predictable.
At 16 tools the set is slightly above the typical well-scoped range, but each tool covers a distinct statutory or payroll scenario and there is little obvious filler. The breadth reflects a genuinely broad Japan payroll/tax domain.
Coverage is strong across payroll, bonus, social insurance, retirement tax, consumption tax, crypto tax, overtime, dependent income walls, mortgage, and business-day calculations. Minor gaps remain, such as no standalone resident/income-tax calculator and sample product names that do not correspond to exposed tools, but core workflows are covered.
Mart402 product catalog: all products, prices, payment config, error codes, rate limits. Free.
Inputs: no named parameters. Returns: body, status, how_to_pay, receipt_id, +1 more
Re-fetch a previously paid result for free by receipt id (every paid response carries receipt_id).
Inputs: receipt_id (required). Returns: body, status, how_to_pay, receipt_id, +1 more
Free recorded sample response for a paid product (from real production runs, marked sample:true) - see the exact response shape before paying anything. Available: document-pipeline, enrich, extract, jp-bonus-net, jp-business-days, jp-company, jp-consumption-tax, jp-crypto-tax, jp-dependent-threshold, jp-mortgage, jp-overtime-wage, jp-payroll-net, jp-payroll-suite, jp-payslip-audit, jp-retirement-tax, jp-social-insurance, meal-vision, ocr, parse, pdf-info, pdf-merge, pdf-pages, portrait-analysis, report-pack, structured, style-profile, style-report, verify.
Inputs: product (required). Returns: body, status, how_to_pay, receipt_id, +1 more
Bonus net pay: social insurance and withholding tax (official rate table, based on previous month salary). $0.01/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Choose this for ONE bonus payment: its social insurance and withholding tax (the tax rate depends on the previous month's salary after social insurance). For annual totals use jp_payroll_net.
Inputs: bonus_yen (required), prefecture (required), age, as_of, +4 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Japanese holidays, business-day arithmetic, statutory filing deadlines with holiday shift, wareki conversion. $0.003/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Required by mode (default add): add -> from, days; between -> from, to; holidays -> year; deadline -> kind, base_date; wareki -> date.
Inputs: to, date, days, from, +6 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Japanese company site to a standard profile JSON (name, address, representative, capital, contact). $0.03/site. Choose this when you have the URL of a Japanese company's OWN site and want its standard profile fields read from the page; for name/domain lookups use enrich_company (country_hint: jp).
Inputs: url (required), x_payment. Returns: body, status, how_to_pay, receipt_id, +1 more
Consumption tax: per-rate invoice rounding, qualified-invoice validation, simplified taxation, 20% special. $0.01/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Required by mode (default invoice_totals): invoice_totals -> lines; validate_invoice -> document; simplified -> taxable_sales_excl_yen, category; two_percent -> taxable_sales_excl_yen, taxable_period_start, taxable_period_end.
Inputs: mode, as_of, lines, category, +5 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Japan crypto-asset tax: realized income under the NTA total-average or moving-average method (sell/spend/exchange as disposals, fees deductible), verified against the official NTA FAQ examples. $0.05/call. Deterministic, cites primary sources; errors and unverified rules are never billed.
Inputs: transactions (required), year, as_of, method, +3 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Income-wall analysis: tax, social insurance (1.06M/1.30M), spousal and student-dependent walls. $0.02/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Choose this for 'how much can be earned before ...' questions: it locates the income walls (tax, social insurance, spousal, student dependent) for an annual income. It does not compute take-home pay (use jp_payroll_net).
Inputs: annual_income_yen (required), year, as_of, x_payment. Returns: body, status, how_to_pay, receipt_id, +1 more
Mortgage schedules (level payment/principal), total interest, prepayment effect. $0.005/call. Deterministic, cites primary sources; errors and unverified rules are never billed.
Inputs: months (required), annual_rate (required), principal_yen (required), method, +2 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Overtime premium pay (Labor Standards Act Art.37, official rounding notice) and Article-36 limit check. $0.015/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Required by mode (default pay): pay -> monthly_salary_yen, monthly_scheduled_hours, hours; check36 -> monthly_overtime_hours.
Inputs: mode, hours, x_payment, monthly_salary_yen, +2 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Annual gross salary to net take-home (social insurance + income tax + resident tax). Exact NTA Beppyo-5 table. $0.02/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Choose this for a whole YEAR: annual gross salary to annual take-home after social insurance, income tax and resident tax. For one bonus use jp_bonus_net; for one month's premiums only use jp_social_insurance; to check an actual payslip use jp_payslip_audit.
Inputs: prefecture (required), annual_gross_yen (required), age, year, +4 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Japan payroll suite: net salary + social insurance + income walls (+bonus) in one call. Flat $0.05. Choose this when you want take-home pay, social insurance and the income walls (and the bonus, if given) together from one annual figure in one call; if you only need the take-home amount, jp_payroll_net is cheaper.
Inputs: prefecture (required), annual_gross_yen (required), age, x_payment, +3 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Audit a Japanese payslip: recompute statutory premiums and withholding tax from official tables and diff against the actual amounts, with per-item verdicts (match/explainable/mismatch). $0.02/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Choose this when you HAVE an actual payslip and want each deduction checked against the official tables (match/explainable/mismatch); to compute expected amounts from a salary alone use jp_payroll_net or jp_social_insurance.
Inputs: payslip (required), prefecture (required), age, as_of, +2 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Retirement income tax: deduction by years of service, half-taxation rules, exact withholding rounding. $0.02/call. Deterministic, cites primary sources; errors and unverified rules are never billed.
Inputs: payout_yen (required), years_of_service (required), x_payment, disability, +1 more. Returns: body, status, how_to_pay, receipt_id, +1 more
Monthly social insurance premiums from the official Kyokai-Kenpo grade table (FY2026). $0.01/call. Deterministic, cites primary sources; errors and unverified rules are never billed. Choose this when you only need the monthly social insurance premiums for a given monthly remuneration (official grade table); no tax is computed - for take-home pay use jp_payroll_net.
Inputs: prefecture (required), monthly_remuneration_yen (required), age, as_of, +1 more. Returns: body, status, how_to_pay, receipt_id, +1 more
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Japan regulatory, sanctions & DEX market data for AI agents via x402 (USDC on Base).
Japan business days & holidays (official Cabinet Office data). Free tool + x402 USDC paid tools.
Every Mart402 tool in one endpoint: PDF parsing and OCR (Japanese-strong), web extraction, invoice checks, Japan statutory calculations and calibrated vision. x402 (USDC on Base), no API key; failed calls are never charged. Focused endpoints: Mart402 Documents & Web, Japan Statutory, Vision and Free tools.
Raw Japanese regulatory data for AI agents: pension, gazette, gBizINFO. x402-metered (USDC).
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