10K Races in Colorado
Colorado has 54 upcoming 10K races scheduled for 2026. Most of the calendar falls in the warmer months: 33 of 54 races (61%) take place between May and September, with September (11 events) the busiest month. Centennial is the busiest city with 27 races, ahead of Windsor (3) and Denver (3).
10K races by month in Colorado
Sep (11) · Aug (9) · Jul (8) · Nov (8) · Oct (7) · Jun (5) · Dec (5) · Mar (1)
Showing 24 of 54
Running
Berthoud Gastro-Dash 10k
Berthoud, CO
Running
Berthoud Gastro-Dash 10k
July 23, 2026
Berthoud, CO
Running
Golden Harvest Half Marathon & 5k/10k - Colorado Springs
September 6, 2026
Colorado Springs, CO
Top Cities for 10K Races in Colorado
Frequently asked questions
How long is a 10K race?▾
A 10K is 6.2 miles (10 kilometers). It is a popular step-up distance from the 5K and a great intermediate goal for runners building toward a half marathon.
What is the largest 10K in the US?▾
The AJC Peachtree Road Race in Atlanta is the largest 10K in the world, drawing over 60,000 runners every Fourth of July. The BOLDERBoulder in Colorado is another massive 10K with 45,000+ participants.
What is a good 10K time?▾
The average US 10K finish time is around 55-60 minutes. Competitive runners aim for sub-45 minutes, while beginners often target finishing under 1 hour 10 minutes.
How do I train for a 10K?▾
A typical 10K training plan is 8-10 weeks with 3-4 runs per week, including one longer run that builds to 6-7 miles. If you can comfortably run a 5K, you are ready to start training for a 10K.