MonsiTools
Type a formula in plain words. Chain the answers.
MonsiTools is a calculator and workflow builder for founders, freelancers and online sellers.
Type how an answer is worked out, like price - product cost - shipping, and each word becomes a labelled field with a live result. Formulas can use brackets, powers, if/else and functions like min, max and round.
Then chain calculators into a workflow. Each step can use an earlier result, so MRR turns into runway and then a valuation without copying numbers between tabs.
You can start from scratch or from a ready-made template. A JSON API and an MCP server let Claude, ChatGPT, Google Sheets and Zapier run the same calculators.
Features
- Build a calculator by typing the formula in plain words
- Chain calculators so one result feeds the next step
- Compare two scenarios side by side and see which input moves the answer most
- Save values like MRR or a day rate and reuse them anywhere
- Export a workflow run as a PDF report
- Run calculators from an AI assistant through the MCP server, or from code through the API
Use Cases
- An online seller checks profit per order after marketplace fees and shipping
- A SaaS founder goes from MRR to runway to a rough valuation
- A freelancer turns a day rate into yearly income and monthly take-home pay
- A marketer checks whether ad spend clears break-even ROAS
- A developer lets an AI agent call exact calculations instead of guessing the math
Comments
Hi everyone, I'm Raian, the solo founder of MonsiTools, based in Dhaka. I built it because most calculator sites give you one answer, and real decisions usually take several. You type the formula the way you'd say it, like price - product cost - shipping, and it becomes a calculator with labelled fields. Then you can chain calculators so each answer carries into the next step, for example MRR into runway and then a rough valuation. There's also a JSON API and an MCP server, so Claude or ChatGPT can run the same calculators instead of doing the arithmetic themselves. I'd like to hear which formula you'd try first, and anything that breaks.
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Comments
Hi everyone, I'm Raian, the solo founder of MonsiTools, based in Dhaka. I built it because most calculator sites give you one answer, and real decisions usually take several. You type the formula the way you'd say it, like price - product cost - shipping, and it becomes a calculator with labelled fields. Then you can chain calculators so each answer carries into the next step, for example MRR into runway and then a rough valuation. There's also a JSON API and an MCP server, so Claude or ChatGPT can run the same calculators instead of doing the arithmetic themselves. I'd like to hear which formula you'd try first, and anything that breaks.
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