VDOT Calculator: Training Paces & Race Time Predictions

Struggling to set training paces that match your current fitness? Not sure what goal time to target at your next marathon?

Setting accurate training paces is critical to maximizing your results. Run too fast and you won’t complete the session; run too slow and you won’t get the intended adaptation.

This guide walks you through the VDOT calculator — the tool built on Jack Daniels’ Running Formula — and shows you exactly how to use it.

Note: VDOT (pronounced V-dot-O-two) is an abbreviation derived from VO2 max.

By the end of this article, you’ll be able to calculate training paces tailored to your current fitness and predict race times for any distance.

What the VDOT Calculator Shows You

The VDOT calculator is a tool that estimates your current VDOT from your race results. Beyond giving you your VDOT score, it simultaneously provides the following information based on your race performance.

The calculator estimates training paces tailored to your current VDOT and can also predict your equivalent time at any other race distance.

The VDOT calculator assumes a strong positive correlation between VO2 max and long-distance race performance.

Research aggregating large datasets confirms that VO2 max and long-distance performance are significantly correlated.

For recreational runners looking to objectively assess their fitness and set appropriate training paces, the VDOT calculator is an outstanding tool worth using regularly.

The VDOT calculator is available as a desktop browser tool and a smartphone app — I’ll cover both below.

Why You Need the VDOT Calculator in Your Training

Here’s when and why to reach for the VDOT calculator.

For tempo runs and interval training, setting paces based on your current fitness is essential. Maximizing training adaptations requires accurate pace targets.

When targeting your lactate threshold and VO2 max, volume matters just as much as intensity. Set your paces too hard and you won’t complete the planned volume — which means fewer total adaptations, not more.

One of the most common mistakes is setting training paces based on your goal race time rather than your current fitness.

Paces derived from a future goal time will likely be too fast to sustain in training. If you can already hit those paces consistently, you’re probably already capable of running that time.

The calculator also accounts for temperature. Hot and cold conditions affect what paces you can sustain, so adjusting your VDOT for heat helps you plan training loads more accurately across the seasons.

Predicting race performance from your training results is equally important. Without a solid, data-based estimate, you risk going out too fast — turning a promising race into an early blowup.

For all these reasons, the VDOT calculator is one of the most valuable tools in a runner’s toolkit.

How to Use the VDOT Calculator on Desktop

Let’s dive in. Here’s how to use the VDOT calculator in your desktop browser.

Basic Input Steps

On the calculator’s homepage, follow these steps:

In the example below, I entered a half marathon time of 1:14:40. After clicking Calculate, the Race Paces tab opens automatically. My VDOT shows as 63.2.

The Race Paces tab displays split times for each set distance based on your input.

Click the Training tab to see the recommended pace for each training type.

For my half marathon PR of 1:14:40, the calculator shows a T pace (Threshold pace) of 5:40/mile(3:31/km).

That means 5:40/mile is my target pace for tempo runs.

The Equivalent tab shows predicted times for other race distances based on the VDOT calculated from your input.

In this example, a half marathon time of 1:14:40 corresponds to an equivalent full marathon time of 2:36:14.

Keep in mind that equivalent times are estimates — actual results will vary depending on whether you’re naturally stronger at shorter or longer distances.

Temperature and Altitude Correction

The VDOT calculator can adjust your score for the temperature and altitude at which you raced. Without any input, it assumes conditions of 15°C (59°F) or below and an elevation of 750m or less.

Click Advanced Features below the Calculate button and follow these steps:

After entering the temperature and clicking Calculate, you’ll get a temperature-adjusted result. Don’t forget to click Reverse after Calculate.

In the example below, I’ve entered a half marathon time of 1:14:40 run in 30°C heat to find the equivalent performance in cool (≤15°C) conditions.

If that 1:14:40 was run in 30°C, the equivalent cool-weather performance would be VDOT 66.4 — a predicted half marathon time of 1:11:33.

Summer heat makes fast times nearly impossible. Use this feature to understand how a summer race result would translate in cooler conditions.

Without pressing Reverse, the calculator answers the opposite question: “What would my cool-weather 1:14:40 look like in 30°C heat?”

The result: a cool-weather 1:14:40 half marathon would translate to roughly 1:17:47 in 30°C conditions.

This is handy for setting realistic goals when you have a summer race and only have winter results to work from. The same steps apply for altitude correction.

Note: Make sure to select ℃ for temperature and m (meters) for altitude.

How to Use the VDOT App on Mobile

The mobile app is even simpler to use than the desktop version. Download the VDOT O2 app on your smartphone before you start.

Open the app, select your event, enter your time in half-width numbers, leave the toggle set to Off, and tap the Calculate button.

The example below uses a half marathon time of 1:14:40. The Training tab shows your pace targets for each workout type; the Equivalent tab shows predicted times for other distances.

To apply temperature or altitude correction in the app, tap the Altitude or Temperature button.

Then enter your values — the process works the same way as on the desktop version.

VDOT Training Pace Chart

The VDOT calculator lets you compute training paces from any race result. I’ve used the same formula to put together a comprehensive VDOT pace table covering a wide range of VDOT values.

Download the VDOT Pace Chart

The Excel version is available for instant download via the button below.

The PDF version opens in your browser first — click the download icon shown below to save it.

On mobile, bookmark it or save it as a file so you can access it anytime.

More Training Paces Beyond the Calculator

The VDOT pace chart includes training paces that the online calculator doesn’t display directly.

The calculator gives you your T pace (Threshold pace) for tempo runs, but leaves a gap: what should you do when you’re running faster than M pace (Marathon pace) but slower than T pace?

Research shows that extending your running duration at a pace slightly below T pace can produce the same stimulus as a 20-minute T-pace run.

The chart also covers the full E pace (Easy pace) range and CV pace — paces the online calculator doesn’t output. Use the table to fill those gaps.

Use VDOT to Identify Your Running Type

One powerful application of the VDOT calculator is identifying whether you’re naturally stronger at shorter or longer distances.

For example, if your full marathon personal record gives you a VDOT of 60 but your 5000m PR gives you a VDOT of 58, your higher marathon VDOT suggests you’re built for longer distances.

Knowing your type helps you identify where to focus your training.

If your 5000m VDOT lags behind your marathon VDOT, improving your 5K speed could unlock faster marathon times.

The VDOT calculator gives you an objective, data-driven view of where you stand.

The VDOT Calculator: Measure Your Running Fitness Objectively

Factors like age can affect how closely the calculator’s suggested paces match your actual training needs.

Treat the output as a starting point, especially when beginning a new type of workout, then adjust based on how the sessions actually feel.

Personally, I find the calculator most useful for predicting race times from workouts I’ve successfully completed in training.

Pacing is everything in distance racing. Going out too fast doesn’t just make the race harder — it wrecks your finishing time and masks other factors when you review the race afterward.

Use the VDOT calculator consistently to track your fitness, set realistic race goals, and build a foundation for steady improvement. The more honestly you assess your current level, the more you’ll get out of every race.

If you haven’t used it yet, give it a try.