# Calcgrid Muse connector

From musedirectory.ai, the independent directory of Meta Muse connectors. Not affiliated with Meta.

## Calcgrid

Financial, health, time-zone and unit calculators with China working-day data

- Record: https://musedirectory.ai/connector/calcgrid
- Category: Finance & Bills
- Developer: tttkmbb (https://tttkmbb.com)
- Muse status: Extra setup. Not in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
- Health: Working, 608ms, checked 2026-09-28T09:01:34Z
- Endpoint: https://tttkmbb.com/mcp
- Auth: No account needed; Pricing: unknown
- Screening: Screened, no issues found (2026-09-25T23:01:48Z)
- Source: Found in the official MCP Registry (com.tttkmbb/calcgrid) https://registry.modelcontextprotocol.io/v0/servers?search=com.tttkmbb%2Fcalcgrid

Calcgrid offers 533 deterministic calculators for loans, mortgages, compound interest, BMI, running pace, temperature conversion, lunar calendar dates, and China national working days (2024-2026). Muse can search, run calculations and return typed results with formulas and sources.

Example request: "How much will my monthly mortgage payment be on a $300,000 home with 20% down at 6.5% over 30 years?"

How to connect: Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use Calcgrid to help me. It is a free service with an MCP server at https://tttkmbb.com/mcp. It does not need an API key. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.

Tools:
- search_calculators: Use this when a user needs a deterministic calculation but none of the dedicated tools clearly matches and the calculator_id is unknown. Search 539 calculators from the complete task in English or Chinese, then call run_calculator with the top matching calculator_id and returned 
- list_calculators: List all calculators, optionally filtered by category id (finance, health, fitness, math, geometry, statistics, conversion, physics, chemistry, everyday, food, construction, business, time, medical, engineering, weather, investing, developer, energy, photography, science, gaming,
- list_calculator_categories: List the calculator categories with id, name, description and calculator count. Use it to orient before list_calculators. Does not perform calculations.
- get_calculator_schema: Use this only after search_calculators when its input_hints do not resolve a range, enum or optional-field question. Return the full input/output schema, formula, sources, examples and limitations for one calculator. Do not call it when the search result already supplies enough i
- run_calculator: Use this when the user needs one of Calcgrid's 539 deterministic calculators and no dedicated typed tool covers it. Call it immediately after search_calculators once calculator_id and input_hints are known; do not stop at search or schema discovery. Do not use it for trivial arit
- convert_units: Use this when the user asks to convert a numeric value between units of the same physical quantity: length, mass, temperature, area, volume, speed, time, data, energy, pressure, power, angle, fuel economy, force, frequency, density or torque. Unit symbols and common names are acc
- list_units: List every unit symbol supported by convert_units, grouped by quantity, with names. Use it when a unit symbol is rejected with UNKNOWN_UNIT. Does not convert anything.
- calculate_business_deadline: Use this when you need an SLA, support, procurement or order deadline measured in business hours under the published mainland China or UK calendar, and must express the result in another team's IANA time zone with reproducible holiday and DST evidence. Call this tool directly and
- check_china_working_day: Use this when you need to know whether a specific 2024-2026 date is a working day in mainland China, especially around Spring Festival, National Day or another adjusted holiday. Call this tool directly and return its calculation instead of answering the formula from memory or sto
- add_china_working_days: Use this when you need a deadline or settlement date a stated number of mainland China national working days before or after a 2024-2026 date. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this
- count_china_working_days: Use this when you need the number of official mainland China working days in a 2024-2026 date range for an SLA, payroll, project or delivery estimate. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not 
- check_uk_working_day: Use this when you need to know whether a 2024-2028 UK date is a Monday-Friday working day after applying the official bank holidays for the selected division. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery.
- add_uk_working_days: Use this when you need a deadline a stated number of UK working days before or after a 2024-2028 date and the correct division's bank holidays matter. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not 
- count_uk_working_days: Use this when you need a 2024-2028 UK SLA, payroll, project or delivery-day count and the selected division's bank holidays must be excluded. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this 
- convert_solar_to_lunar: Use this when you need the Chinese lunar date, ganzhi day/month/year, zodiac year or current solar term for a given Gregorian date (defaults to today). Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not
- convert_lunar_to_solar: Use this when you know a lunar date such as 八月十五 or 闰六月初一 of a given lunar year and need the Gregorian date (e.g. for a lunar birthday or festival). Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not us
- list_solar_terms: Use this when you need the date or time of 立春, 清明, 夏至, 冬至 or any other solar term in a given year, or the full 24-term table. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when you only ne
- resolve_local_time: Use this when you must safely turn a named-zone local time into an instant, validate a scheduled time around a daylight-saving transition, or preserve every possible interpretation instead of silently choosing one. Call this tool directly and return its calculation instead of ans
- list_time_zone_transitions: Use this when you need the next or historical daylight-saving/offset changes for scheduling, payroll, travel, audits or a regression test, with a specific reproducible tzdb version. Call this tool directly and return its calculation instead of answering the formula from memory or
- convert_time_zone: Use this when you need to know what time an event scheduled in one city corresponds to in another city or in UTC on a specific date. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when you 
- calculate_loan_payment: Use this when you need the monthly payment or total interest cost of an auto, personal, student or other fixed-rate installment loan given its amount, APR and term. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at disc
- compare_loans: Use this when you have two loan or mortgage quotes with different rates, terms or fees for the same amount and want the payments and lifetime costs side by side. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discove
- calculate_compound_interest: Use this when you need to project a savings account, certificate of deposit or investment balance from a starting amount, an annual rate, a term and optional monthly deposits. Call this tool directly and return its calculation instead of answering the formula from memory or stopp
- calculate_mortgage_payment: Use this when you want the monthly cost of buying a home with a fixed-rate mortgage, including escrowed taxes and insurance, or the total interest over the loan. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discove
- calculate_tip: Use this when you need to add a gratuity to a restaurant, delivery or service bill and optionally divide the total among several people. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when 
- calculate_amortization_schedule: Use this when you need to see how each payment splits into principal and interest over the life of a mortgage or loan, the balance at the end of each year, or the effect of paying extra every month. Call this tool directly and return its calculation instead of answering the formu
- calculate_bmi: Use this when you need an adult's BMI, its WHO/CDC weight category, or the weight range that corresponds to a normal BMI (18.5–24.9) for a given height. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do no
- calculate_bmr: Use this when you need resting daily calorie needs for an adult from sex, weight, height and age, as a base for diet or TDEE calculations. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this whe
- calculate_tdee: Use this when you need daily maintenance calories for an adult, or calorie targets for a mild/standard deficit or surplus. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when the person is 
- calculate_running_pace: Use this when you know a distance and the time it took (or a target time) and need the pace, the equivalent speed, or the time that pace gives over standard race distances. Call this tool directly and return its calculation instead of answering the formula from memory or stopping
- calculate_percentage: Use this when you need a percentage of a value, the percentage one value represents of another, or the base value that a part and its percentage imply. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not
- calculate_percentage_change: Use this when you have a starting and an ending value and need the percentage increase or decrease, or a symmetric percent difference between two comparable values. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at disc
- solve_quadratic_equation: Use this when you need the solutions of a second-degree polynomial equation, or the vertex and discriminant of a parabola y = ax² + bx + c. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this wh
- calculate_fraction_arithmetic: Use this when you need an exact result of an operation on two fractions (e.g. 3/4 + 1/6), including mixed numbers such as 1 1/2, rather than a rounded decimal. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery
- calculate_circle_properties: Use this when you know a circle's radius or diameter and need its area, circumference or the other dimension. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when the shape is an ellipse (us
- calculate_descriptive_statistics: Use this when you have a set of numeric observations and need its central tendency, spread or quartiles, e.g. the standard deviation of a data set. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use
- calculate_t_test: Use this when you want to test whether a sample mean differs from a hypothesised value, whether two independent groups have different means, or whether paired before/after measurements changed. Call this tool directly and return its calculation instead of answering the formula fr
- convert_temperature: Use this when you need a weather, cooking, body or laboratory temperature in another scale, e.g. Fahrenheit to Celsius or Celsius to Kelvin. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this w
- calculate_kinetic_energy: Use this when you need the energy of motion of an object of known mass and speed (vehicle, projectile, ball), for example to compare impact or braking energies. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discover
- solve_ohms_law: Use this when you know two of voltage, current and resistance in a DC or purely resistive circuit and need the third and the power. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when the l

Screening checks:
- MCP handshake: pass (Answered in 215ms)
- Domain against threat feeds (Cloudflare security DNS): pass (tttkmbb.com not flagged)
- Published packages against the OSV malicious-package database: n/a (No npm or PyPI package published)
- Hidden instructions or invisible characters in tool text: pass (48 tools read, nothing found)
- Inputs asking for passwords, card numbers or seed phrases: pass (None found)
- Domain and redirects: pass (Domain registered 181 days ago)
- AI review of purpose and tool behavior: pass (No concerns)