The Ultimate Reusable Functions and Advanced Options Toolkit for Excel

Admin
Sep 12, 2025
3 min read

Excel has been around for decades, but it’s still one of the most powerful tools for analytics, reporting, and automation. While most users stop at VLOOKUP or SUMIFS, there’s a whole new world of advanced reusable functions, dynamic arrays, and hidden tricks that can supercharge your workflows.

This post is all about building an Excel Toolkit — a set of reusable functions, advanced formulas, and automation hacks you can apply again and again across workbooks.

Excel Toolkit: A comprehensive set of tools designed to enhance productivity and data analysis within Microsoft Excel, featuring a variety of icons symbolizing utility and functionality.

Why Build a Toolkit in Excel?

Consistency: Use the same tested logic across multiple reports.
Efficiency: Save hours by automating repetitive calculations.
Scalability: Handle thousands of rows with ease.
Flexibility: Dynamic functions adapt as data changes.

Think of it as your personal “function library” — like a developer would use in programming.

Part 1: Reusable Functions (Formulas)

Here are some “must-have” reusable formulas for your toolkit.

Function	Use Case	Formula Example
XLOOKUP	Replace old VLOOKUP/HLOOKUP with more flexible searches	=XLOOKUP("ProductA", A2:A100, B2:B100, "Not Found")
SEQUENCE	Generate dynamic ranges, dates, IDs	=SEQUENCE(12,1,1,1) → 1 to 12
TEXTSPLIT	Split strings without helper columns	=TEXTSPLIT(A2, ",")
UNIQUE	Quickly extract distinct values	=UNIQUE(A2:A100)
FILTER	Create dynamic filtered tables	=FILTER(A2:C100, B2:B100="Germany")
LET	Define variables inside formulas	=LET(x,SUM(A2:A100), y,COUNT(A2:A100), x/y)
LAMBDA	Create your own reusable custom function	Example below 👇

Part 2: Custom Reusable Functions with LAMBDA

Excel’s LAMBDA function is a game-changer. It lets you define your own custom function (without VBA).

Example: A reusable function to calculate the CAGR (Compound Annual Growth Rate).

=LAMBDA(StartValue, EndValue, Periods, (EndValue/StartValue)^(1/Periods)-1)

Create the function in a cell.
Name it in Name Manager (e.g., CAGR).
Reuse it everywhere:
=CAGR(1000, 2500, 5)

Result: 19.97% annual growth.

This way, you build a library of custom functions: CAGR, % Change, Margin %, Working Days, etc.

Part 3: Advanced Toolkit Tricks

Beyond functions, here are advanced tricks to include in your toolkit:

1. Dynamic Named Ranges

Use =OFFSET or =INDEX to create ranges that grow with your data.

Example:

=OFFSET(Sheet1!$A$2,0,0,COUNTA(Sheet1!$A:$A)-1,1)

Now, charts and pivots auto-update as new rows are added.

2. Reusable Data Validation Lists

Instead of static dropdowns, link validation lists to =UNIQUE(Table1[Country]). They’ll update automatically as new countries appear.

3. Combine Functions for “Smart” Reports

Example: Dynamic KPI Status Flag

=IF(A2>=Target,"✅ On Track","⚠️ Behind")

Add icons/conditional formatting → instant dashboard indicators.

4. Office Scripts + Power Automate

If you’re on Microsoft 365, extend your toolkit beyond formulas:

Use Office Scripts to automate repetitive Excel steps.
Trigger them with Power Automate (e.g., auto-refresh a file, export to PDF, send report by email).

Example: Script to remove all blank rows across sheets, reusable in any workbook.

Example: The Ultimate “Reusable Toolkit” Setup

Imagine you manage monthly sales data. Instead of rebuilding calculations:

Use UNIQUE to list all products.
Use SUMIFS or FILTER to calculate sales per product.
Apply your custom CAGR function to track growth.
Add a conditional format with KPIs (✅/⚠️).
Automate refresh with Power Automate.

Result: A dynamic, reusable sales dashboard you can copy into any workbook.

Conclusion

Excel is no longer just about static formulas — with dynamic arrays, LAMBDA, and automation you can build a personalized toolkit of reusable functions.

Start small: pick 3–5 functions you use daily, convert them into reusable formulas, and expand over time. Soon, you’ll have your own Excel library ready for any project.

Here’s a ready-to-use demo file for the blog: