> For the complete documentation index, see [llms.txt](https://docs.gpmautomate.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.gpmautomate.com/automate-en/action-guides/blocks/for.md).
# For
#### Configuration parameters in the For loop:
* 🟢 Start: The starting value of the loop variable `$loopIndex`.
* 🔴 End: The ending value. The loop will stop when `$loopIndex` reaches the value `End - 1`.
* âš¡ Increase by: The step (increment value) of `$loopIndex` after each completed iteration.
#### Practical example: Combining the For loop to read all data from an Excel file
Suppose you have an Excel file named `test.xlsx` and you need to configure a script to read all the data in column B of this file. You can combine the For loop with the system variable `$inputExcelTotalRows` as follows:
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