Flight Reliability
F9 4345 · Frontier Airlines
Denver → Los Angeles (DEN–LAX)
74
Usually Fine
WanderNerd Reliability Score
- 71%
- Arrive within 15 minutes
- 10 min
- Average arrival delay
- 1.3%
- Cancelled
- 5 min early
- Median arrival delay
Based on 305 historical flights. Data through May 2026.
What the data says
Friday is doing you no favors.
F9 4345 arrived on time 79% of the time on Wednesdays and just 62% on Fridays. That gap is worth planning around.
Lagging the DEN–LAX route.
F9 4345 arrived on time 71% of the time, versus 80% across the DEN–LAX route.
Trending in the right direction.
F9 4345 arrived on time 84% of the time over the last three months in the data, compared with 66% in the three months before that.
The breakdown
- Mon67%(52 flights)
- Tue77%(34 flights)
- Wed79%(34 flights)
- Thu77%(48 flights)
- Fri62%(50 flights)
- Sat63%(32 flights)
- Sun77%(51 flights)
95%
May
Jun 57% → May 95% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 57% | 28 |
| July 2025 | 50% | 30 |
| August 2025 | 59% | 29 |
| September 2025 | 73% | 26 |
| October 2025 | 87% | 30 |
| November 2025 | 83% | 30 |
| December 2025 | 55% | 20 |
| January 2026 | 59% | 17 |
| February 2026 | 84% | 19 |
| March 2026 | 79% | 29 |
| April 2026 | 77% | 22 |
| May 2026 | 95% | 21 |
- Departures on time
- 66%
- Diverted
- 0%
- Flights flown
- 301
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 305 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.