Quarterly Tax Calculator for ChatGPT

io.github.al157/quarterlytax-mcp

US federal + state quarterly estimated tax estimates, SE tax, and quarterly payment due dates.

client:ChatGPT transport:streamable-http tools:2

Install Quarterly Tax Calculator in ChatGPT

Settings → Connectors → Advanced → Developer mode

https://mcp.quarterlytax.al157.xyz/mcp

Custom connectors are a paid-plan feature and take a remote URL only. ChatGPT cannot run a packaged server locally. ChatGPT docs