# Excel University Blog

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# Comparison Formulas

## Highlight Correct Answer with Conditional Formatting

| February 6, 2024 |

Time to walk through another exciting Excel adventure 🙂 Today, we’re zooming in on an interesting question I recently received: “How can I highlight correct answers on an Excel worksheet for my granddaughter’s multiplication tables?” Sounds like a marvelously practical application of Excel, doesn’t it? Well, let’s dive in and find out how we can…

## How to Find Invalid Characters

| January 2, 2024 |

Welcome to this tutorial on how to find invalid characters in Microsoft Excel. In this tutorial, we will explore different methods including formulas and conditional formatting to detect and highlight characters you define as “invalid” in your Excel worksheets. Since you can easily customize the list of “invalid” characters, this approach is extremely flexible and…

## Excel How to Sum Values Between Dates

| October 24, 2023 |

This tutorial shows how to use the SUMIFS function to sum the amounts for records that fall between two dates. By the end of this tutorial, you will be able to enter the desired date range into two input cells, and have Excel immediately sum the values that fall between these dates, even if the…

## Excel How to Count Cells between dates

| October 17, 2023 |

This tutorial demonstrates how to count the number of date cells that fall between two specific dates using COUNTIFS. We will start with a simple exercise using a single condition and gradually progress to more complex exercises involving multiple conditions and comparison operators. By the end of this tutorial, you will be able to perform…