Turn an Excel spreadsheet into a REST API in 5 minutes

Most companies already keep their hardest-won logic — pricing, quotes, risk scoring, engineering calculations — inside Excel. The problem is never the spreadsheet; it is getting that logic out of the file and into the products, workflows, and apps that need it. With Businesslogic you publish a workbook as a REST API without touching a line of code.

What you need

• An Excel file that takes some inputs and produces outputs.
• A free Businesslogic account (14-day trial, no card required).
• Five minutes.

Step 1 — Upload your workbook

Sign in and upload the .xlsx file. Your formulas, named ranges, and sheets are preserved exactly as they are. Nothing is rewritten and nothing leaves your control.

Step 2 — Mark inputs and outputs

Point at the cells that should become request parameters (the inputs) and the cells that hold the results (the outputs). That mapping is the whole "API design" step — Businesslogic generates the JSON schema for you.

Step 3 — Call your endpoint

Your service is now live with two endpoints: /execute runs the model with the inputs you send, and /describe returns the input/output schema so other systems can integrate automatically.

curl -X POST https://api.businesslogic.online/execute \
  -H "X-Auth-Token: <your-token>" \
  -H "Content-Type: application/json" \
  -d '{ "salary_per_month": 4200, "start_year": 2026 }'

Why this beats rewriting it in code

• The business owner keeps editing the model in Excel — no developer round-trip for every change.
• Developers integrate against a stable JSON contract and never need to understand the formulas behind it.
• There is one source of truth, so the website, the mobile app, and the back office all compute the same answer.

Ready to try it? Start your free trial and publish your first Excel API today.