{"success":true,"version":"v1","request":{"tool":"list_calculators","category":"investing"},"result":{"entity_type":"calculator_list","status":"completed","count":19,"calculators":[{"calculator_id":"black-scholes","entity_type":"calculator","name":"Black-Scholes Option Calculator","category":"investing","tool_name":"price_black_scholes_option","description":"Prices a European call and put with the Black-Scholes-Merton formula from spot, strike, time to expiry, risk-free rate, volatility and a continuous dividend yield, and reports d1, d2 and the Greeks (delta, gamma, vega, theta, rho).","use_when":"You need a theoretical European option price or its sensitivities from a given volatility, or want to check put-call parity for quoted prices.","do_not_use_when":"The option is American with early exercise value, the underlying pays discrete dividends, or you need implied volatility from a market price (solve numerically instead). Informational only; not financial advice.","required_inputs":["spot_price","strike_price","time_years","risk_free_rate_percent","volatility_percent"],"optional_inputs":["dividend_yield_percent"],"urls":{"html":"https://tttkmbb.com/investing/black-scholes","markdown":"https://tttkmbb.com/investing/black-scholes.md","schema":"https://tttkmbb.com/api/v1/calculators/black-scholes","api":"https://tttkmbb.com/api/v1/calculate/black-scholes"}},{"calculator_id":"capm","entity_type":"calculator","name":"CAPM Calculator","category":"investing","tool_name":"calculate_capm_expected_return","description":"Computes the expected return of an asset with the capital asset pricing model (CAPM) from the risk-free rate, the asset's beta and the expected market return, plus the equity risk premium and the beta-scaled premium.","use_when":"You need a required or expected return for a stock or portfolio given its beta, for example as the cost of equity in a DCF or WACC calculation.","do_not_use_when":"The asset's beta is unknown or unstable, or you need a multi-factor return (Fama-French) rather than the single-factor CAPM. Informational only; not financial advice.","required_inputs":["risk_free_rate_percent","beta","market_return_percent"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/capm","markdown":"https://tttkmbb.com/investing/capm.md","schema":"https://tttkmbb.com/api/v1/calculators/capm","api":"https://tttkmbb.com/api/v1/calculate/capm"}},{"calculator_id":"sharpe-ratio","entity_type":"calculator","name":"Sharpe Ratio Calculator","category":"investing","tool_name":"calculate_sharpe_ratio","description":"Computes the Sharpe ratio of a portfolio from its return, the risk-free rate and the standard deviation of returns, annualizes it for monthly, weekly or daily data and gives a rule-of-thumb interpretation.","use_when":"You want to compare investments or strategies on return per unit of total risk, or annualize a Sharpe ratio measured on periodic data.","do_not_use_when":"You only care about downside risk (use a Sortino ratio) or the return per unit of market risk (Treynor ratio). Informational only; not financial advice.","required_inputs":["portfolio_return_percent","risk_free_rate_percent","standard_deviation_percent"],"optional_inputs":["periods_per_year"],"urls":{"html":"https://tttkmbb.com/investing/sharpe-ratio","markdown":"https://tttkmbb.com/investing/sharpe-ratio.md","schema":"https://tttkmbb.com/api/v1/calculators/sharpe-ratio","api":"https://tttkmbb.com/api/v1/calculate/sharpe-ratio"}},{"calculator_id":"two-asset-portfolio","entity_type":"calculator","name":"Two-Asset Portfolio Calculator","category":"investing","tool_name":"calculate_two_asset_portfolio","description":"Computes the expected return, variance and standard deviation of a two-asset portfolio from the weights, expected returns, standard deviations and correlation, and finds the minimum-variance weight and the diversification benefit.","use_when":"You want to see how combining two assets (e.g. stocks and bonds) changes risk and return, or find the weight that minimises portfolio variance.","do_not_use_when":"The portfolio has more than two assets (a covariance matrix is needed) or you want the tangency (maximum Sharpe) portfolio. Informational only; not financial advice.","required_inputs":["weight_a_percent","return_a_percent","return_b_percent","std_dev_a_percent","std_dev_b_percent","correlation"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/two-asset-portfolio","markdown":"https://tttkmbb.com/investing/two-asset-portfolio.md","schema":"https://tttkmbb.com/api/v1/calculators/two-asset-portfolio","api":"https://tttkmbb.com/api/v1/calculate/two-asset-portfolio"}},{"calculator_id":"dcf-valuation","entity_type":"calculator","name":"DCF Valuation Calculator","category":"investing","tool_name":"calculate_dcf_valuation","description":"Projects free cash flow at a constant growth rate for a number of years, discounts each year and a Gordon-growth terminal value at the discount rate, and reports enterprise value, equity value (after net debt) and value per share.","use_when":"You want an intrinsic value of a company or project from its current free cash flow, a growth assumption, a discount rate (e.g. WACC) and a terminal growth rate.","do_not_use_when":"Cash flows are irregular or already listed year by year (use npv), the company has negative free cash flow, or you want the rate of return of known flows (use irr). Informational only; not financial advice.","required_inputs":["current_free_cash_flow","growth_rate_percent","discount_rate_percent","terminal_growth_percent"],"optional_inputs":["projection_years","shares_outstanding","net_debt"],"urls":{"html":"https://tttkmbb.com/investing/dcf-valuation","markdown":"https://tttkmbb.com/investing/dcf-valuation.md","schema":"https://tttkmbb.com/api/v1/calculators/dcf-valuation","api":"https://tttkmbb.com/api/v1/calculate/dcf-valuation"}},{"calculator_id":"gordon-growth","entity_type":"calculator","name":"Gordon Growth Model Calculator","category":"investing","tool_name":"calculate_gordon_growth_value","description":"Values a stock as the next dividend divided by the required return minus the dividend growth rate (Gordon growth model), and when a price is given, reports the implied return and whether the price is above or below the intrinsic value.","use_when":"You want an intrinsic value for a stable, dividend-paying stock from its dividend, expected growth and required return, or the return implied by its current price.","do_not_use_when":"The company pays no dividend, growth is not constant (use dcf-valuation) or growth is at or above the required return. Informational only; not financial advice.","required_inputs":["required_return_percent","growth_percent"],"optional_inputs":["next_dividend","current_dividend","current_price"],"urls":{"html":"https://tttkmbb.com/investing/gordon-growth","markdown":"https://tttkmbb.com/investing/gordon-growth.md","schema":"https://tttkmbb.com/api/v1/calculators/gordon-growth","api":"https://tttkmbb.com/api/v1/calculate/gordon-growth"}},{"calculator_id":"wacc","entity_type":"calculator","name":"WACC Calculator","category":"investing","tool_name":"calculate_wacc","description":"Computes the weighted average cost of capital from the market values and costs of equity, debt and optional preferred stock, applying the corporate tax shield to the cost of debt.","use_when":"You need a discount rate for a company's cash flows, or want to see how the debt/equity mix and tax rate change the overall cost of capital.","do_not_use_when":"You only need the cost of equity itself (use capm) or the capital structure changes over the forecast period. Informational only; not financial advice.","required_inputs":["equity_value","debt_value","cost_of_equity_percent","cost_of_debt_percent","tax_rate_percent"],"optional_inputs":["preferred_value","cost_of_preferred_percent"],"urls":{"html":"https://tttkmbb.com/investing/wacc","markdown":"https://tttkmbb.com/investing/wacc.md","schema":"https://tttkmbb.com/api/v1/calculators/wacc","api":"https://tttkmbb.com/api/v1/calculate/wacc"}},{"calculator_id":"bond-duration","entity_type":"calculator","name":"Bond Duration Calculator","category":"investing","tool_name":"calculate_bond_duration","description":"Prices a fixed-coupon bond from its yield to maturity and computes Macaulay duration, modified duration, convexity, DV01 and the estimated price change for a 1 percentage-point rise in yield.","use_when":"You want to know how sensitive a bond's price is to interest-rate changes, or need duration and convexity for hedging or portfolio matching.","do_not_use_when":"You know the price and want the yield (use bond-yield), or the bond is callable, floating-rate or amortizing. Informational only; not financial advice.","required_inputs":["coupon_rate_percent","yield_to_maturity_percent","years_to_maturity"],"optional_inputs":["face_value","coupons_per_year"],"urls":{"html":"https://tttkmbb.com/investing/bond-duration","markdown":"https://tttkmbb.com/investing/bond-duration.md","schema":"https://tttkmbb.com/api/v1/calculators/bond-duration","api":"https://tttkmbb.com/api/v1/calculate/bond-duration"}},{"calculator_id":"cap-rate","entity_type":"calculator","name":"Cap Rate Calculator","category":"investing","tool_name":"calculate_cap_rate","description":"Computes a property's net operating income from gross income, vacancy and operating expenses, and divides it by the price to get the capitalization rate, alongside the gross yield.","use_when":"You want to compare income properties on unlevered return, or turn an asking price and rent roll into a cap rate.","do_not_use_when":"You want the return on the cash actually invested after mortgage payments (use cash-on-cash-return) or a quick price-to-rent screen (use gross-rent-multiplier). Informational only; not financial advice.","required_inputs":["property_price","annual_gross_income"],"optional_inputs":["annual_operating_expenses","vacancy_percent"],"urls":{"html":"https://tttkmbb.com/investing/cap-rate","markdown":"https://tttkmbb.com/investing/cap-rate.md","schema":"https://tttkmbb.com/api/v1/calculators/cap-rate","api":"https://tttkmbb.com/api/v1/calculate/cap-rate"}},{"calculator_id":"cash-on-cash-return","entity_type":"calculator","name":"Cash-on-Cash Return Calculator","category":"investing","tool_name":"calculate_cash_on_cash_return","description":"Computes a rental property's annual pre-tax cash flow after operating expenses and debt service, and divides it by the cash invested (down payment, closing costs, repairs) to get the cash-on-cash return.","use_when":"You financed a rental property and want the yield on the actual cash you put in, including the effect of the mortgage.","do_not_use_when":"You want an unlevered, financing-independent comparison (use cap-rate) or a total return including appreciation and principal paydown. Informational only; not financial advice.","required_inputs":["cash_invested","annual_rental_income","annual_operating_expenses"],"optional_inputs":["annual_debt_service"],"urls":{"html":"https://tttkmbb.com/investing/cash-on-cash-return","markdown":"https://tttkmbb.com/investing/cash-on-cash-return.md","schema":"https://tttkmbb.com/api/v1/calculators/cash-on-cash-return","api":"https://tttkmbb.com/api/v1/calculate/cash-on-cash-return"}},{"calculator_id":"gross-rent-multiplier","entity_type":"calculator","name":"Gross Rent Multiplier Calculator","category":"investing","tool_name":"calculate_gross_rent_multiplier","description":"Divides a property's price by its annual gross rent to get the gross rent multiplier (GRM), the number of years of gross rent needed to pay the price, together with the gross yield.","use_when":"You want a quick screen of an income property's price relative to its rent, or to compare listings before analysing expenses.","do_not_use_when":"Operating expenses or vacancy matter for the decision (use cap-rate) or the property is financed and you want the return on your cash (use cash-on-cash-return). Informational only; not financial advice.","required_inputs":["property_price"],"optional_inputs":["annual_gross_rent","monthly_rent"],"urls":{"html":"https://tttkmbb.com/investing/gross-rent-multiplier","markdown":"https://tttkmbb.com/investing/gross-rent-multiplier.md","schema":"https://tttkmbb.com/api/v1/calculators/gross-rent-multiplier","api":"https://tttkmbb.com/api/v1/calculate/gross-rent-multiplier"}},{"calculator_id":"rental-yield","entity_type":"calculator","name":"Rental Yield Calculator","category":"investing","tool_name":"calculate_rental_yield","description":"Annualizes a weekly, monthly or annual rent and computes the gross rental yield on the property value and the net yield after annual expenses and purchase costs, plus the monthly net income.","use_when":"You want the yield of a buy-to-let or investment property from its rent and value, in the gross form quoted by agents or the net form after costs.","do_not_use_when":"You need the return on the cash invested with a mortgage (use cash-on-cash-return) or a commercial-style NOI cap rate with vacancy (use cap-rate). Informational only; not financial advice.","required_inputs":["property_value","rent_amount"],"optional_inputs":["rent_period","annual_expenses","purchase_costs"],"urls":{"html":"https://tttkmbb.com/investing/rental-yield","markdown":"https://tttkmbb.com/investing/rental-yield.md","schema":"https://tttkmbb.com/api/v1/calculators/rental-yield","api":"https://tttkmbb.com/api/v1/calculate/rental-yield"}},{"calculator_id":"mortgage-affordability","entity_type":"calculator","name":"Mortgage Affordability Calculator","category":"investing","tool_name":"calculate_mortgage_affordability","description":"Applies the front-end (housing) and back-end (total debt) debt-to-income limits to gross income, subtracts taxes and insurance to get the affordable principal-and-interest payment, and converts it into a maximum loan amount and home price for the given rate and term.","use_when":"You want to know how much house or mortgage an income supports under standard lender ratios, before applying for a loan.","do_not_use_when":"You already have a loan amount and want its payment (use mortgage-payment) or want to check ratios for an existing payment (use debt-to-income). Lender rules vary; informational only, not financial advice.","required_inputs":["annual_gross_income","interest_rate_percent"],"optional_inputs":["monthly_debt_payments","down_payment","term_years","front_end_ratio_percent","back_end_ratio_percent","monthly_taxes_insurance"],"urls":{"html":"https://tttkmbb.com/investing/mortgage-affordability","markdown":"https://tttkmbb.com/investing/mortgage-affordability.md","schema":"https://tttkmbb.com/api/v1/calculators/mortgage-affordability","api":"https://tttkmbb.com/api/v1/calculate/mortgage-affordability"}},{"calculator_id":"position-sizing","entity_type":"calculator","name":"Position Size Calculator","category":"investing","tool_name":"calculate_position_size","description":"Computes how many shares (or units) to buy or short so that hitting the stop-loss loses a fixed percentage of the account, using the fixed-fractional method: risk amount divided by the risk per share.","use_when":"You have an entry and stop-loss price and want the number of shares that keeps the potential loss at a chosen fraction of the account.","do_not_use_when":"You want the mathematically optimal fraction to bet from a known edge (Kelly criterion) or the reward side of the trade (use risk-reward-ratio). Informational only; not financial advice.","required_inputs":["account_size","risk_percent","entry_price","stop_loss_price"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/position-sizing","markdown":"https://tttkmbb.com/investing/position-sizing.md","schema":"https://tttkmbb.com/api/v1/calculators/position-sizing","api":"https://tttkmbb.com/api/v1/calculate/position-sizing"}},{"calculator_id":"risk-reward-ratio","entity_type":"calculator","name":"Risk/Reward Ratio Calculator","category":"investing","tool_name":"calculate_risk_reward_ratio","description":"Computes the risk and reward per share from an entry, stop-loss and target price, the reward-to-risk ratio and the win rate at which such trades break even.","use_when":"You are planning a trade with a stop and a target and want to know whether the potential gain justifies the risk, or the minimum hit rate the setup needs.","do_not_use_when":"You need the number of shares to trade (use position-sizing) or the expected value of a bet with known odds. Informational only; not financial advice.","required_inputs":["entry_price","stop_loss_price","target_price"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/risk-reward-ratio","markdown":"https://tttkmbb.com/investing/risk-reward-ratio.md","schema":"https://tttkmbb.com/api/v1/calculators/risk-reward-ratio","api":"https://tttkmbb.com/api/v1/calculate/risk-reward-ratio"}},{"calculator_id":"dca-average-cost","entity_type":"calculator","name":"Dollar-Cost Averaging Calculator","category":"investing","tool_name":"calculate_dca_average_cost","description":"Simulates investing a fixed amount at each of a list of prices, and reports the units bought, the average cost per unit (harmonic mean of prices), the simple average price, the current value at the last price and the gain or loss.","use_when":"You invest the same amount every period and want your true average cost, or want to see how a fixed-amount plan compares with the average price.","do_not_use_when":"You buy a fixed number of units each time (the average cost is then the simple average price) or want a projection with a growth rate (use compound-interest). Informational only; not financial advice.","required_inputs":["amount_per_period","prices"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/dca-average-cost","markdown":"https://tttkmbb.com/investing/dca-average-cost.md","schema":"https://tttkmbb.com/api/v1/calculators/dca-average-cost","api":"https://tttkmbb.com/api/v1/calculate/dca-average-cost"}},{"calculator_id":"max-drawdown","entity_type":"calculator","name":"Maximum Drawdown Calculator","category":"investing","tool_name":"calculate_max_drawdown","description":"Scans a series of portfolio or equity values in time order for the largest percentage fall from a running peak, reporting the peak and trough values and positions, whether the peak was regained, and the drawdown at the end of the series.","use_when":"You want the worst historical loss of a strategy, fund or portfolio from a list of values, or the current distance below its high-water mark.","do_not_use_when":"You need volatility-based risk (use sharpe-ratio or descriptive-statistics) or your data are period returns rather than values (convert them to a cumulative value series first). Informational only; not financial advice.","required_inputs":["values"],"optional_inputs":[],"urls":{"html":"https://tttkmbb.com/investing/max-drawdown","markdown":"https://tttkmbb.com/investing/max-drawdown.md","schema":"https://tttkmbb.com/api/v1/calculators/max-drawdown","api":"https://tttkmbb.com/api/v1/calculate/max-drawdown"}},{"calculator_id":"expense-ratio-impact","entity_type":"calculator","name":"Expense Ratio Impact Calculator","category":"investing","tool_name":"calculate_expense_ratio_impact","description":"Grows an initial investment with optional annual contributions at a gross return minus a fund's expense ratio, compares it with a lower-cost alternative, and reports the total fee cost and its share of the final value.","use_when":"You want to see how much a fund's annual expense ratio costs over decades, or compare two funds with different fees on the same investment plan.","do_not_use_when":"You need a plain growth projection without fees (use compound-interest) or a comparison including loads, trading costs and taxes. Informational only; not financial advice.","required_inputs":["initial_investment","years","annual_return_percent","expense_ratio_percent"],"optional_inputs":["annual_contribution","comparison_expense_ratio_percent"],"urls":{"html":"https://tttkmbb.com/investing/expense-ratio-impact","markdown":"https://tttkmbb.com/investing/expense-ratio-impact.md","schema":"https://tttkmbb.com/api/v1/calculators/expense-ratio-impact","api":"https://tttkmbb.com/api/v1/calculate/expense-ratio-impact"}},{"calculator_id":"valuation-ratios","entity_type":"calculator","name":"Stock Valuation Ratios Calculator","category":"investing","tool_name":"calculate_valuation_ratios","description":"Computes the common per-share valuation ratios of a stock from its price and fundamentals: price-to-earnings and earnings yield, price-to-book, price-to-sales, dividend yield and payout ratio, PEG and EV/EBITDA, each only when its inputs are supplied.","use_when":"You have a share price and per-share fundamentals and want the standard multiples to compare a stock with peers or its own history.","do_not_use_when":"You want an intrinsic value from cash flows or dividends (use dcf-valuation or gordon-growth) or a dividend income projection (use dividend-yield). Informational only; not financial advice.","required_inputs":["share_price","earnings_per_share"],"optional_inputs":["book_value_per_share","sales_per_share","dividend_per_share","earnings_growth_percent","enterprise_value","ebitda"],"urls":{"html":"https://tttkmbb.com/investing/valuation-ratios","markdown":"https://tttkmbb.com/investing/valuation-ratios.md","schema":"https://tttkmbb.com/api/v1/calculators/valuation-ratios","api":"https://tttkmbb.com/api/v1/calculate/valuation-ratios"}}]},"timestamp":"2026-09-24T03:46:49Z","next_actions":[],"links":{"docs":"https://tttkmbb.com/calculators.md"}}