Spreadsheet Day

The Spreadsheet Day is celebrated every year on 17 October in recognition of the launch of the first electronic spreadsheet program, VisiCalc, in 1979. This day honors one of the most practical and transformative tools in modern computing—used by millions daily for organizing, analyzing, and making sense of data. From accountants and small business owners to students and scientists, spreadsheets are the unsung backbone of productivity, and Spreadsheet Day gives them a moment in the spotlight.

History of Spreadsheet Day

Spreadsheet Day was established in 2010 by Debra Dalgleish, a spreadsheet expert and blogger who wanted to celebrate how integral spreadsheets have become in both professional and everyday life. After a poll to choose the best date, 17 October was selected because it marked the anniversary of the release of VisiCalc, the first spreadsheet program for personal computers.

VisiCalc, short for “visible calculator”, was developed by Dan Bricklin and Bob Frankston and was released for the Apple II computer. It revolutionized how people managed numbers—suddenly, a tool existed where changing one number could automatically update related values in real-time. This breakthrough laid the groundwork for modern spreadsheet software like Microsoft Excel, Google Sheets, and others. What started as a simple tool for business planning is now an everyday essential used in homes, offices, schools, and research labs around the world.

Why Spreadsheet Day is important

Spreadsheets are more than just rows and columns—they’re flexible thinking tools. They let people organize chaos, explore scenarios, and visualize trends. Whether you’re managing a household budget or tracking lab results, spreadsheets give you control and clarity over data. And this day reminds us how significant that is. Without spreadsheets, so many processes—from payroll to planning—would be slower, harder, and prone to error.

At the same time, Spreadsheet Day is a chance to think about how we use these tools. Are we building clean, understandable spreadsheets? Do we teach others how to use them well? A single error in a formula can lead to big consequences, so part of honoring the spreadsheet is encouraging smarter habits: double-checking logic, labeling clearly, and sharing knowledge. It’s a good day to remind ourselves that how we build and use spreadsheets matters, and that data literacy is something worth celebrating.

Why people enjoy this day:

• It celebrates a tool that’s quietly changed the world
• It encourages learning new spreadsheet tricks and tips
• It highlights the creativity possible with data modeling
• It builds appreciation for how we handle information
• It’s a fun excuse to geek out over formulas and shortcuts

How to Observe Spreadsheet Day

You don’t need to be a spreadsheet wizard to celebrate. One easy way is to explore a new function—maybe SUMIF, VLOOKUP, or a pivot table—and see how it can simplify your work. Or revisit a spreadsheet you use often and tidy it up: fix formatting, double-check calculations, and add notes. It’s surprisingly satisfying.

If you’re in a team or office, try running a quick “spreadsheet lunch” where people share tips, clever tricks, or useful templates. You might also challenge yourself to automate something tedious with a formula. And if you’re someone who already loves spreadsheets, share the love: help a friend build one for their side project, or post a tip online.

Some things you can do to mark the day:

• Learn a new formula and teach it to someone
• Fix up an old spreadsheet you use all the time
• Share a cool template or shortcut with your team
• Try using conditional formatting to visualize something
• Post a quick spreadsheet tutorial or tip online

Spreadsheet Day Dates Table