Sunrise and Sunset times in Boulder, United States 
Today:
 Sunrise: 07:26:48
|
 Sunset: 17:06:18
|
Day Length: 9h 39m 30s
Time zone: America/Denver, UTC -7 h.
Latitude: 37.9228, Longitude: -111.432
Boulder
Utah, United States 
240 people
| Date | Sunrise | Solar Noon | Sunset | Day length |
|---|---|---|---|---|
| 2025-Dec-01, Monday | 07:23:10 | 12:14:57 | 17:06:44 | 9h 43m 34s |
| 2025-Dec-02, Tuesday | 07:24:06 | 12:15:20 | 17:06:34 | 9h 42m 28s |
| 2025-Dec-03, Wednesday | 07:25:01 | 12:15:44 | 17:06:27 | 9h 41m 26s |
| 2025-Dec-04, Thursday | 07:25:55 | 12:16:08 | 17:06:21 | 9h 40m 26s |
| 2025-Dec-05, Friday | 07:26:48 | 12:16:33 | 17:06:18 | 9h 39m 30s |
| 2025-Dec-06, Saturday | 07:27:40 | 12:16:58 | 17:06:16 | 9h 38m 36s |
| 2025-Dec-07, Sunday | 07:28:31 | 12:17:24 | 17:06:17 | 9h 37m 46s |
| 2025-Dec-08, Monday | 07:29:21 | 12:17:51 | 17:06:20 | 9h 36m 59s |
| 2025-Dec-09, Tuesday | 07:30:10 | 12:18:18 | 17:06:25 | 9h 36m 15s |
| 2025-Dec-10, Wednesday | 07:30:57 | 12:18:45 | 17:06:32 | 9h 35m 35s |
| 2025-Dec-11, Thursday | 07:31:43 | 12:19:13 | 17:06:42 | 9h 34m 59s |
| 2025-Dec-12, Friday | 07:32:28 | 12:19:41 | 17:06:53 | 9h 34m 25s |
| 2025-Dec-13, Saturday | 07:33:11 | 12:20:09 | 17:07:07 | 9h 33m 56s |
| 2025-Dec-14, Sunday | 07:33:53 | 12:20:38 | 17:07:22 | 9h 33m 29s |
| 2025-Dec-15, Monday | 07:34:33 | 12:21:07 | 17:07:40 | 9h 33m 7s |
| 2025-Dec-16, Tuesday | 07:35:12 | 12:21:36 | 17:07:59 | 9h 32m 47s |
| 2025-Dec-17, Wednesday | 07:35:49 | 12:22:05 | 17:08:21 | 9h 32m 32s |
| 2025-Dec-18, Thursday | 07:36:25 | 12:22:35 | 17:08:44 | 9h 32m 19s |
| 2025-Dec-19, Friday | 07:36:59 | 12:23:04 | 17:09:10 | 9h 32m 11s |
| 2025-Dec-20, Saturday | 07:37:31 | 12:23:34 | 17:09:37 | 9h 32m 6s |
| 2025-Dec-21, Sunday | 07:38:01 | 12:24:04 | 17:10:06 | 9h 32m 5s |
| 2025-Dec-22, Monday | 07:38:30 | 12:24:34 | 17:10:37 | 9h 32m 7s |
| 2025-Dec-23, Tuesday | 07:38:57 | 12:25:03 | 17:11:10 | 9h 32m 13s |
| 2025-Dec-24, Wednesday | 07:39:21 | 12:25:33 | 17:11:45 | 9h 32m 24s |
| 2025-Dec-25, Thursday | 07:39:44 | 12:26:03 | 17:12:21 | 9h 32m 37s |
| 2025-Dec-26, Friday | 07:40:06 | 12:26:33 | 17:12:59 | 9h 32m 53s |
| 2025-Dec-27, Saturday | 07:40:25 | 12:27:02 | 17:13:39 | 9h 33m 14s |
| 2025-Dec-28, Sunday | 07:40:42 | 12:27:31 | 17:14:21 | 9h 33m 39s |
| 2025-Dec-29, Monday | 07:40:57 | 12:28:00 | 17:15:04 | 9h 34m 7s |
| 2025-Dec-30, Tuesday | 07:41:10 | 12:28:29 | 17:15:48 | 9h 34m 38s |
| 2025-Dec-31, Wednesday | 07:41:22 | 12:28:58 | 17:16:34 | 9h 35m 12s |
Day length in Boulder during the year on the chart:
Boulder on United States map:
Locations in the same time zone America/Denver
Denver (Colorado), Salt Lake City (Utah), El Paso (Texas), Albuquerque (New Mexico), Colorado Springs (Colorado), Ogden (Utah), Provo (Utah), Aurora (Colorado), Fort Collins (Colorado), Lakewood (Colorado), Pueblo (Colorado), Thornton (Colorado), Grand Junction (Colorado), West Valley City (Utah), Las Cruces (New Mexico), Greeley (Colorado), Billings (Montana), Arvada (Colorado), St. George (Utah), West Jordan (Utah), Westminster (Colorado), Centennial (Colorado), Santa Fe (New Mexico), Highlands Ranch (Colorado), Logan (Utah), Longmont (Colorado), Orem (Utah), Rio Rancho (New Mexico), Sandy (Utah), Lafayette (Colorado)
Largest populated areas in United States
New York (New York), Los Angeles (California), Chicago (Illinois), Miami (Florida), Dallas (Texas), Philadelphia (Pennsylvania), Houston (Texas), Washington (District of Columbia), Atlanta (Georgia), Boston (Massachusetts), Phoenix (Arizona), Seattle (Washington), San Francisco (California), Detroit (Michigan), San Diego (California), Minneapolis (Minnesota), Tampa (Florida), Denver (Colorado), Brooklyn (New York), Queens (New York), Baltimore (Maryland), Riverside (California), St. Louis (Missouri), Las Vegas (Nevada), Portland (Oregon), San Antonio (Texas), Sacramento (California), San Jose (California), Orlando (Florida), Cleveland (Ohio)
Countries closest to United States
*Calculation of distances from capital to capital
Daylight Hours FAQ: 10 Most Googled Questions Answered
Daylight hours refer to the period between sunrise and sunset. This duration changes throughout the year based on season and geographic location.
Earth's 23.5° axial tilt causes uneven sunlight distribution. Your hemisphere receives less direct sunlight in winter (shorter days) and more in summer (longer days).
Northern Hemisphere: June 20-22 (summer solstice).
Southern Hemisphere: December 21-23.
Near polar circles, the sun doesn't set for 24 hours.
Northern Hemisphere: December 21-22 (winter solstice).
Southern Hemisphere: June 20-21.
The closer to poles, the more extreme variations:
- Equator: ~12-hour days year-round
- Polar regions: Midnight sun/polar nights occur
Miami's lower latitude means:
- Winter days are longer than NY's
- Summer days are slightly shorter
During equinoxes:
- Spring: March 20-21
- Fall: September 22-23
Most rapid change near equinoxes: 2-4 minutes daily.
Slowest change near solstices: <1 minute daily.
Reliable tools:
- Timeanddate.com
- SunCalc.org
- Photographer's Ephemeris app
Yes. Reduced winter sunlight may cause:
- Seasonal Affective Disorder (SAD)
- Vitamin D deficiency
Solution: Light therapy lamps & midday walks