Frequently Asked Questions

Common questions about Numstro

DOES NUMSTRO STORE MY DATA?

No. Numstro does not store your uploaded spreadsheet data. All processing happens in memory only, and your data is discarded immediately after processing. We never save your files, formulas, or any personal information to our servers.

DOES NUMSTRO CALCULATE FORMULAS?

No. Numstro generates Excel formulas but does not calculate results. The formulas are ready to copy and paste into Excel or Google Sheets, where they will calculate using your actual data. This approach ensures compatibility and accuracy.

WHAT FILE TYPES ARE SUPPORTED?

Numstro supports:

  • CSV files (.csv)
  • Excel files (.xlsx, .xls)
  • Pasted data - You can copy cells from Excel and paste directly into Numstro

Limits: Files up to 1,000 rows and 100 columns. Only cell values are imported—formulas and formatting are not preserved.

IS NUMSTRO FREE?

Yes, Numstro is currently free during early access. All features are available at no cost, with no usage limits. We may introduce paid tiers in the future with advanced features, but early access users will be notified before any changes. See our pricing page for more details.

WHAT AI MODEL POWERS NUMSTRO?

Numstro uses OpenAI's GPT-4o-mini model for formula generation and explanation. This model is specifically tuned for accuracy and efficiency in generating Excel formulas based on your data structure and questions.

WHY IS MY GENERATED FORMULA NOT WORKING IN EXCEL?

Common reasons formulas might not work:

  • Column references: Make sure the column letters match your actual spreadsheet layout
  • Data types: Ensure your data is formatted correctly (numbers as numbers, dates as dates)
  • Range sizes: All ranges in functions like SUMIFS must be the same size
  • Syntax errors: Check for typos or missing quotes around text criteria
  • Excel version: Some newer functions (like XLOOKUP) require Excel 365 or Excel 2021

If you're having trouble, try the Formula Explainer to understand what the formula should do, then verify your data matches the expected format.

CAN I USE NUMSTRO FOR COMMERCIAL PURPOSES?

Yes. Numstro can be used for both personal and commercial purposes. There are no restrictions on commercial use. However, always verify that generated formulas work correctly in your specific use case before relying on them for critical business decisions.

WHAT EXCEL FUNCTIONS DOES NUMSTRO SUPPORT?

Numstro can generate formulas using a wide range of Excel functions, including:

  • SUM, SUMIF, SUMIFS
  • AVERAGE, AVERAGEIF, AVERAGEIFS
  • COUNT, COUNTIF, COUNTIFS
  • VLOOKUP, HLOOKUP, XLOOKUP
  • INDEX, MATCH
  • IF, IFS, SWITCH
  • Text functions: LEFT, RIGHT, MID, LEN, CONCATENATE
  • And many more

See our Supported Functions page for a complete list.

HOW ACCURATE ARE THE GENERATED FORMULAS?

Numstro's AI is trained on Excel syntax and common use cases, but accuracy depends on how clearly you describe what you want to calculate. The AI analyzes your column headers and sample data to match your question to the right formula. Always test formulas in Excel before using them in production. If a formula doesn't work as expected, try rephrasing your question or checking the Formula Explainer to understand what it's trying to do.

CAN I SAVE MY FORMULAS IN NUMSTRO?

Not currently. Numstro doesn't have user accounts or saved formulas yet. You can copy generated formulas and paste them into Excel or save them elsewhere. Saved formulas may be available in future paid tiers.