Servers by gumballtools

Row-by-row loan amortization schedules: monthly or daily accrual, extra principal, PMI, biweekly.

Words-in-context vocabulary practice questions with distractor explanations.

Convert height and weight, compute BMI, TDEE and protein targets with error bounds.

Validates IBAN/ISBN/EAN/Luhn checksums and finds the one wrong digit

Convert colours between hex, RGB, HSL, OKLCH and CMYK, and compute harmonies.

Estimate a due date from LMP, conception, or ultrasound, with ACOG redating rules.

ISO 8601 week numbers: date to week, week to date, weeks-per-year.

Convert JSON samples into TypeScript interfaces and Zod schemas, with inference caveats.

Validate JSON, YAML, XML and CSV with exact line/column errors and silent-corruption warnings.

Round cash totals to the nearest nickel correctly — after tax, on the total, cash only.

One MCP server exposing every tool in the Gumball portfolio.

Step-by-step solver for linear/quadratic equations in one variable, signs and ± always right.

Explain a regex in plain English and detect catastrophic backtracking risk.

Work an offside call through IFAB Law 11 or NHL Rule 83, step by step.

Convert times between IANA zones and detect skipped or ambiguous DST local times.