How To Estimate A Marathon Time

When you’re estimating something, it is never going to be exact but you can try and get it as close as possible.trying to predict your marathon time is quite difficult but there are two different ways you can go around this.

How To Estimate A Marathon Time

Predicting your marathon race time is not the easiest thing to do because there are many factors that can affect you on the actual day. 

This guide will be covering both methods in full to help you make sure you can give your family and friends a time to be waiting for you at the finishing line, to cheer you on.

Even though it might not be to the exact second, the more marathons you do, the predictions you make will become more and more accurate over time. 

For more information on different ways to predict your running time, all of the relevant info is down below where you can also find out more about the importance of keeping on track of your health and diet the whole way through your training for maximum results.

What Are The Different Methods?

There are two different methods you can use to try and predict your marathon time. 

There is the original predicting method which includes a more mathematical approach which was created by Pete Riegel.

T2 = T1 x (D2/D1)1.06 is the equation you will be using to predict the amount of time it will take you to run the marathon. It works by:

  • T1 is the given time 
  • D1 is the distance 
  • D2 is the distance to predict a time for 
  • T2 is the calculated time for D

Many people use this way to predict their time for the marathon but it does come with some limitations. This type of prediction is a better way for elite runners to use because it is more realistic for them.

However, it can be very unrealistic for people who are not regular runners. The reason for it sometimes being unrealistic for most people is because it does not count for things happening during the race.

For example, if you were to need the toilet, this would take time off and also get stitches throughout the race. This will slow you down in certain parts of the race and something you need to consider in the time.

You will need to account for these different factors that will add time onto your run and can sometimes make a big difference to the time.

Method 2

The second method is more of a practical session to determine how long it would take you to run the race. This is known as the Yasso 800s which is an intense session that would be completed 2 weeks before the race.

You need to do 10x800m with a 400m recovery jog in between each of the reps. This has become a more effective way of predicting the amount of time it would take you to run a marathon because it takes more into account.

This is a really difficult session and definitely isn’t for the faint hearted and will be testing high endurance levels and your speed too. 

This doesn’t always work for everyone because some people are great at mastering their recovery and the environment of an actual marathon is quite different in the sense of what you go through and what you have to push through. 

How Else Can You Prepare For The Race?

How Else Can You Prepare For The Race?

When doing this type of training before a race you also need to keep your diet balanced and filled with nutrition to fuel your body. You also need to focus heavily on keeping your body properly hydrated throughout your training as well as the race day.

If you are not looking after your body throughout training, you will not be able to get a clear prediction of how long it will take you to run the race. 

Why Should You Calculate Your Time?

It is essential that you try and predict the amount of time it will take you to run the marathon first so you are able to pace yourself throughout the race.

Your body will know its limits and you will know how fast you can run and when your body starts to slow. You also need to factor in other aspects of the race such as weather conditions and difficulty.

The run will be different to what you’re running in the training, different levels of difficulty. This is why experience comes into it heavily.

When people have been running marathons for a long time, they get to know their running style and the course. This allows them to learn how to predict their speed and endurance over time as a professional runner. 


Overall, when trying to predict the amount of time it will take you to run a marathon, there are factors that need to be considered. You need to be looking at the weather conditions, your fitness, health, diet and hydration.

You also need to factor in your pace during the race, needing to go to the toilet, what you’ve eaten on the day. It is all really important information needed to get as close to your prediction as you can.

The main word that comes to mind is consistency with training and diet. 

Hopefully this guide has given some insight into two different methods you can use to attempt to predict your marathon run time. They are never going to be 100% accurate because of the factors that were mentioned before.

It also tends to be much easier the more experienced you are because you are able to know your ability better in the actual conditions you’ll be running in. 

Frequently Asked Questions

How Do I Predict My Marathon Time?

Marathon coach Hal Higdon suggests finding your marathon finish time by multiplying your 10K time by five if you are a first-timer, or 4.66 if you are an experienced marathoner.

Dr. John Robinson suggests a different approach. He says that you can add 20 seconds to your mile each time you double your distance.

How Long Does It Take For An Average Person To Run A Marathon?

4 to 5 hoursAcross the board, most people finish a marathon in 4 to 5 hours, with an average mile time of 9 to 11.5 minutes.

A finishing time that’s under 4 hours is a real accomplishment for everyone other than elite runners, who can finish in around 2 hours.

Jessica Knight