WorkbookAPI

Let your AI agent calculate with your Excel model.

WorkbookAPI checks your Excel model in the browser for free, with a calculation API for your AI agent planned for early access. A plausible estimate is not the same as a calculated result.

Check your workbook — free, it never leaves your browser

The assistant needs the model's math.

An analyst may ask an assistant for a payback period, quote, or forecast. An agent developer needs a calculation tool. Pasting the workbook into a prompt does not check the answer against its formulas.

Why the usual options hurt

Asking an assistant to rewrite formulas creates a second model to maintain. Running Excel on a server adds maintenance. Asking an analyst to calculate each answer by hand limits the assistant's usefulness.

How it works with WorkbookAPI

Drop the model into the free browser check. See which formulas compute exactly like Excel before connecting any agent.

Recalculate and save in Excel first. The check compares against saved results for the current inputs. A match does not prove every possible agent request will be correct.

Today, only the browser check is live. Calculation API access is planned for early access; join the waitlist on the home page.

In the planned workflow, your agent will send explicit inputs and use the returned model outputs in its answer. The analyst keeps the model in Excel. Updating the workbook will update the calculation the agent calls.

Illustration: an assistant answering a payback question

The assistant would ask the model to calculate simple payback using stated assumptions.

This illustrates a planned tool call, not a live agent integration. Correct units and assumptions still matter.

What is not supported

Macros/VBA, Power Query, pivot tables, what-if data tables, and links to other workbooks are not supported. Strict Open XML files are also unsupported. The report flags them.

FAQ

Can an AI agent get exact numbers from my Excel model?

The planned API will return calculated model outputs instead of asking the assistant to estimate them. Check the workbook first, and verify the agent's inputs, units, and interpretation.

Is there a WorkbookAPI MCP server or agent integration today?

No. There is no WorkbookAPI MCP server or ready-made agent integration available.

Does a matching check make the assistant's answer correct?

No. It checks formula results against saved Excel results for one input set. The model's assumptions and the agent's choice of inputs still need review.

Does my model leave my browser during the check?

No. The workbook never leaves your browser during the check. Only anonymous totals are counted, never values, formulas, or file names.

Read the privacy policy.

Start with your workbook

Check your workbook — free, it never leaves your browser

For the calculation workflow, see Excel to API. For many assumptions, see scenario analysis.

All use cases