Calculate Excel formulas without Excel installed.
WorkbookAPI checks your Excel model in the browser for free, with an API for running it from Python, Node, or a server planned for early access. Reading cell values is not enough.
Check your workbook — free, it never leaves your browser
You need calculated answers, not spreadsheet rows.
Your application changes input cells and needs fresh outputs. Reading a workbook's saved values does not calculate a new scenario. The business owner still changes the formulas in Excel.
Why the usual options hurt
A code rewrite leaves developers copying every model change. Running Excel on a server means maintaining that installation and handling calculation jobs. Sending requests to an analyst creates a manual queue.
How it works with WorkbookAPI
Drop the workbook into the free browser check. It needs no local Excel installation to run the check.
See which formulas compute exactly like Excel. Comparison needs results previously saved by Excel, so ask the model owner to recalculate and save first.
Today, only the browser check is live. A calculation API is planned for early access; join the waitlist on the home page.
The planned API will let Python, Node, or another client send inputs and receive outputs. The owner keeps the model in Excel. Updating the workbook will update the API's calculation.
Illustration: a shipping calculation from Node
A checkout service could use an operations team's workbook instead of copying its shipping formulas.
- Inputs: A 12-pound parcel, destination zone 4, and express delivery.
- Outputs: Shipping charge and delivery estimate calculated by the workbook.
This describes the planned API flow.
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 I calculate Excel formulas without Excel installed?
The browser check works without a local Excel installation. It compares calculations with results already saved by Excel.
Can I call my Excel model from Python or Node today?
Not yet. A calculation API is planned.
Is an Excel calculation API the same as reading spreadsheet rows?
No. Reading rows returns stored data. A calculation API takes new inputs, recalculates the model's formulas, and returns new outputs. That is the planned WorkbookAPI workflow.
Does my workbook 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
Need many input sets? See bulk scenario analysis. For tool calls, see AI agent Excel calculation.