calculator
Calculators accessible via MCP with real-time collaborative sessions and shareable URLs.
What it can do
What data it sees
Do you need an account
No: the server works without sign-in
Calculators accessible via MCP with real-time collaborative sessions and shareable URLs.
How to connect
How to connect calculator to Claude
The server address to paste into Claude settings:
https://mcpcalc.com/api/v1/mcp
- Open Claude (claude.ai or the desktop app).
- Go to Settings → Connectors.
- Click Add custom connector.
- Paste the server address copied below into Remote MCP server URL and click Add.
- In a chat, click + → Connectors and switch the new connector on.
Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.
Authorization
After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.
How to connect calculator to ChatGPT
The server address to paste into ChatGPT settings:
https://mcpcalc.com/api/v1/mcp
- Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
- Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
- Open Settings → Connectors and click Create.
- Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
- Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
- In a new chat open + → Apps/Connectors and enable the connector.
OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.
Authorization
On first use ChatGPT opens the service's sign-in window. Sign in and approve access.
How to connect calculator to Cursor
The server address to paste into Cursor settings:
https://mcpcalc.com/api/v1/mcp
Fastest: click Open in Cursor below and confirm the prompt.
Manually:
- In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
- Paste the JSON copied below into
~/.cursor/mcp.json(per project:.cursor/mcp.jsonin the repo root). - Save the file. The server appears in the MCP list; authorize it there if asked.
Authorization
If the service needs sign-in, an authorize button appears next to the server in the MCP list.
Server tool list (10)
Raw names from tools/list. Only developers need these.
| list_calculators | List available calculators, optionally filtered by category |
| get_calculator_schema | Get the input schema for a specific calculator |
| calculate | Run a calculation and get results + prefilled URL |
| generate_prefilled_url | Generate a prefilled URL without running calculation |
| calculate_cas | Evaluate one or more headless CAS expressions server-side (MCP-only numeric mode). Unsupported expressions return a GUI handoff link. |
| calculate_cas_headless | Alias of calculate_cas. Headless MCP-only CAS evaluator; if unsupported features are requested, returns GUI handoff details. |
| create_session | Create a new interactive session for any calculator and return the session URL |
| get_session_state | Retrieve the current field values, computation transcript, and pending message queue for an active session |
| push_session_action | Push actions into a session's message queue (set fields, submit computation, trigger plot, etc.) |
| close_session | Close a session and optionally persist a snapshot of its final state |