Tempo pace is the running pace at or just below the lactate threshold — the fastest pace at which the body can clear lactate as fast as it accumulates. It's often described as "comfortably hard" and is sometimes called the 10-mile or 1-hour race pace.
In Jack Daniels' framework, tempo pace is explicitly defined as "T pace" (Threshold pace) and is derived from VDOT. For a runner with VDOT 50, T pace is approximately 4:14 min/km (6:49 min/mile). The VDOT calculator on this site shows T pace for any input race time.
Tempo runs are a staple of structured distance running training because they improve the lactate threshold — raising the pace at which you can operate aerobically. Common formats: - Tempo run: 20–40 minutes at threshold pace - Cruise intervals: 3–4 × 8–10 minutes at threshold pace with 1-minute jogs
Important note: this site explains what tempo pace is, not how to train with it. Training prescription requires a qualified coach.