This article is based on a conversation with Diarmuid Early, the 40-year-old winner of the 2025 Microsoft Excel World Championship. The text has been edited for length and clarity.
Diarmuid Early won first place at the 2025 Microsoft Excel World Championship.
He tells BUSINESS INSIDER (BI) his Excel tips for everyday office life.
Early runs an Excel consulting firm. He deepened his knowledge at the Boston Consulting Group and Deutsche Bank.
I have been in the Excel business for about 20 years.
I played around with it a bit in college and started using it professionally at Boston Consulting Group. I then worked at Deutsche Bank as a business manager for ten years. There I had a lot to do with data analysis and financial reporting.
I've been self-employed for about six years now, so I've spent pretty much my entire career with Excel.
Winning the Excel World Championship was a great feeling. In the knockout phase I fell short of my potential for a long time. Every year I went into the knockout rounds first or second. In recent years I've made it to the finals in Las Vegas, but I think fifth place was my best finish so far.
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My most important Excel tip
My number one tip for office workers is to always believe that there is a better way.
If you find yourself saying, “Oh God, I've been copying and pasting this for ten minutes and I still have 15 minutes to go,” if you find yourself doing something manually and repeatedly, then there's very likely a better way to do it in Excel.
If you ask Google or ChatGPT for a brief description of what you need, chances are 1,000 or more other people have wanted to do the same thing over the years.
In my experience, if I look, 80 percent of the things I've ever had problems with in Excel, there's a post somewhere describing how to solve them with a reasonably clear description.
If you learn to use the SUMIF function, it will probably take you longer the first time than if you do it by hand. But the second time it's a little faster, the third time it's much quicker – and the thousands of times you'll need it over the course of your career, you'll save a huge amount of time.
It's also much less likely to be wrong or contain unexplained errors than if you did it manually.
It will take a little longer the first time. But if you are the youngest new employee in a company, you are expected to still need time anyway. If you take a long time the first time, but are ten times faster the second time, the gain over six months – not to mention your career – is enormous.
The more you learn about these things and the more you put them together to do more complex things, the more exponential the gain.
Use the time you have gained to take a step back
It's great to be able to say very quickly, “The answer is seven.” If you figure this out quickly, you'll have more time to ask yourself, “Does it even make sense that the answer is seven?”
That's exactly what young bankers and consultants often don't like to do. They see their job as calculating the model and providing a number – while the next person in the hierarchy then asks: What does that mean? What is knowledge? Does that make sense?
If you take the time to do this yourself and then communicate it, you will gain much more credibility. This also makes it much more likely that you will catch your own mistakes before someone else spots them.
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What I find most frightening is when I see a formula that consists of 50 different numbers in the form A1 + B3 + C5 + D10. Someone obviously entered them all by hand or click, click, click.
This takes a lot of time – and the probability that you will make a mistake and make an error that you will never find again is high.
This is one of the easiest ways to get on the wrong path. Basically, at every level of Excel proficiency, there is something you do wrong without even realizing it until you get to the next level.
I believe that AI will be very helpful in taking people from bad to not bad or maybe even from bad to good. For people like me who already have a lot of experience, it probably won't be of much help.
When AI gets to the point where it can teach me new things in Excel, there won't be much room left for human Excel users.
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I know 50,000 tricks. During my time at BCG I did a lot of Excel training. Every now and then you were teaching someone something and you would see this look of mixed joy and horror on their face. She later states: “If I had known that last night, I wouldn’t have had to work until two in the morning.”
This is the person who will never forget what you just taught her.
Source: https://www.businessinsider.de/karriere/excel-weltmeister-verraet-das-ist-mein-tipp-fuer-euren-buero-job/
