Marathon Pace Calculator

This calculator uses the basic running formula: pace = time ÷ distance. Based on your selected mode, it calculates the unknown value from the other two known values. All calculations happen in real-time.

Pace is the time required per kilometer (mi) or mile, typically displayed in 'minutes'seconds'' format. For example, 5'30'' means 5 minutes and 30 seconds per kilometer (or per mile). Lower pace means faster running.

Click the unit toggle button (with the cycle icon) in the top-right of the input area to switch between metric (km) and imperial (mi). All values will convert automatically.

The split times table shows cumulative time at each kilometer (mi) or mile marker throughout your run. This is useful for planning race pacing strategies.

The central pace indicator's color changes based on pace intensity: cool colors (blue, cyan) indicate easy pace, warm colors (orange, red) indicate fast pace. This helps you quickly assess training intensity.

Yes! Both distance and time rings are draggable. Click and drag the progress bar on the ring to adjust values in real-time. It's a fun way to explore different pace combinations.

You can enter any distance, or use the preset buttons for common distances: 5K (3.1 mi), 10K (6.2 mi), Half Marathon (21.0975 km / 13.1 mi), Marathon (42.195 km / 26.2 mi), and 50K (31.1 mi).

Race Phases strategy divides the marathon into four key phases: Start (0-5 km / 0-3.1 mi, 2-5s slower), Cruise (5-30 km / 3.1-18.6 mi, target pace), Decision Zone (30-38 km / 18.6-23.6 mi, +2s), and Final Push (38-42.2 km / 23.6-26.2 mi, -5s faster). Compared to even pacing, this strategy better aligns with human physiological responses and race realities, helping runners manage energy more effectively, avoid early fatigue, and maintain competitiveness at critical moments.

We use the GAP (Grade Adjusted Pace) formula to correct for environmental factors affecting pace. The core formula is: P_adj = P_base × (1 + temp_factor + slope_factor). Temperature correction is based on heat stress index, where high temperatures increase pace. Slope correction is based on vertical elevation gain, where uphill significantly increases pace and downhill reduces it accordingly. These adjustments help you maintain the same physiological intensity under different environmental conditions.

In the split table, we mark water stations (💧) every 2.5 km (1.6 mi) and energy stations (⚡) every 5 km (3.1 mi). We recommend slowing down 100-200 meters (110-220 yards) before energy stations to ensure adequate time for intake. Based on your pace plan, calculate your arrival time at each station in advance, allowing you to execute your fueling strategy more calmly during the race and avoid energy depletion from insufficient fueling.

Click the "Share Poster" button in the calculator to open the Export Center. We support three export formats: 1) Social Card (1:1 ratio), perfect for sharing on social media; 2) A4 Pace Band, which you can print and wear on your wrist during the race to check pace checkpoints anytime; 3) FIT course file, which can be imported into Garmin, Suunto, and other sports watches to receive pace alerts during the race. All export formats include your complete pace plan, split times, and key checkpoint information.