Time for first half = d / 60, second half = d / 40 - High Altitude Science

Understanding the Context

What Do “d/60” and “d/40” Mean in Football?

In football, the full match duration is typically 90 minutes, divided into two 45-minute halves. To calculate halftime timing or pacing, some analysts and scorers use ratios such as d/60 for the first half and d/40 for the second half, where:

• d represents “minutes played” or “played duration”
  - The ratio compares time elapsed relative to the total match time, adjusted for sport-specific pacing.

So, “d/60” during the first half means the first half’s time progression is measured against 60 units per full 90-minute game, while “d/40” in the second half reflects pacing on a 40-unit scale — more condensed but proportionally scaled.

Key Insights

First Half: d / 60 – A Standardized Pace Marker

The d/60 measure for the first half is widely adopted in statistical tracking and broadcast commentary. It does not mean only 60 minutes are tracked—it compares time progression relative to standard performance benchmarks. Coaches and analysts use this ratio to:

• Evaluate team speed and pressure management
  - Compare pacing trends between games
  - Schedule halftime activities with precision

For example, if a first half advances to “d/60” (e.g., 30 minutes elapsed), it signals active transition with moderate intensity, perfectly aligned with the extended first-half timing of 45 minutes (~60 minutes scaled).

Final Thoughts

Second Half: d / 40 – Accelerated Timing for Endurance Management

In contrast, “d/40”” in the second half reflects tighter time scaling, emphasizing endurance and late-game intensity. Since the second half is also 45 minutes (90 total), this 40-unit ratio compresses time relative to performance effort—helping coaches manage fatigue and adjust tactical plans.