Pro lesson · 6 exercises · first one free
Checking cells: ISBLANK, ISNUMBER, ISERROR and IFNA
About this lesson
Test what a cell contains before you calculate with it, and catch only the errors you expect.
Errors and conditions · 6 short exercises in a live spreadsheet: you type each formula yourself and answer questions that make you predict results or spot bugs. Every answer is checked instantly.
What you'll practise
- Testing whether a cell is empty
- Checking whether a value is a number
- Flagging bad entries with IF and ISNUMBER
- Catching only the not found error
- Predicting what ISERROR returns
- Choosing between IFNA and IFERROR
Functions you'll use
Try the first exercise free
Type the formula in a real spreadsheet and get instant feedback. Exercise 1 of 6, no account needed.
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