Convert Coordinated Universal Time to Hawaii Standard Time
Instantly convert Coordinated Universal Time (UTC) to Hawaii Standard Time (HST) with our free online calculator.
Coordinated Universal Time
05:20:58 AM
Wed, Jun 24 (UTC)
Hawaii Standard Time
07:20:58 PM
Tue, Jun 23 (HST)
Convert a Specific Time
24-Hour Comparison
| UTC | HST |
|---|---|
| 12:00 AM | 2:00 PM(-1d) |
| 1:00 AM | 3:00 PM(-1d) |
| 2:00 AM | 4:00 PM(-1d) |
| 3:00 AM | 5:00 PM(-1d) |
| 4:00 AM | 6:00 PM(-1d) |
| 5:00 AM | 7:00 PM(-1d) |
| 6:00 AM | 8:00 PM(-1d) |
| 7:00 AM | 9:00 PM(-1d) |
| 8:00 AM | 10:00 PM(-1d) |
| 9:00 AM | 11:00 PM(-1d) |
| 10:00 AM | 12:00 AM |
| 11:00 AM | 1:00 AM |
| 12:00 PM | 2:00 AM |
| 1:00 PM | 3:00 AM |
| 2:00 PM | 4:00 AM |
| 3:00 PM | 5:00 AM |
| 4:00 PM | 6:00 AM |
| 5:00 PM | 7:00 AM |
| 6:00 PM | 8:00 AM |
| 7:00 PM | 9:00 AM |
| 8:00 PM | 10:00 AM |
| 9:00 PM | 11:00 AM |
| 10:00 PM | 12:00 PM |
| 11:00 PM | 1:00 PM |
How to Convert Coordinated Universal Time to Hawaii Standard Time
Formula
To convert Coordinated Universal Time (UTC) to Hawaii Standard Time (HST): Convert UTC to HST
About Coordinated Universal Time (UTC)
Coordinated Universal Time (UTC) is the primary time standard by which the world regulates clocks and time, defined since 1972 as the time at the Prime Meridian (0° longitude) maintained by BIPM (Bureau International des Poids et Mesures) in Sèvres, France. UTC is computed as a weighted average of approximately 400 atomic clocks at ~80 national metrology institutes (NIST in the US, NPL in UK, PTB in Germany, NICT in Japan, KRISS in Korea, etc.) per the formal definition in ITU-R Recommendation TF.460-6 (2002). UTC is functionally identical to GMT (Greenwich Mean Time) for civil purposes but differs slightly in its underlying timescale — UTC uses atomic seconds with occasional leap seconds inserted (announced by IERS Bulletin C ~6 months in advance, last leap second was December 31, 2016, and the system may be retired by 2035 per Resolution D of CGPM 2022). UTC is the standard for aviation (ICAO Annex 5), maritime navigation (IMO COLREGS), all internet protocols (NTP, PTP per IEEE 1588), all scientific publications, GPS / Galileo / GLONASS / BeiDou GNSS, and Universal Time on Wikipedia/Wikidata.
About Hawaii Standard Time (HST)
Hawaii Standard Time (HST, IANA: Pacific/Honolulu) is the time zone for the State of Hawaii and the Aleutian Islands of Alaska west of 169.5°W. HST is UTC-10:00 year-round and does not observe Daylight Saving Time per Hawaii Revised Statutes §1-31 (Hawaii opted out of the Uniform Time Act of 1966). When the US mainland switches to Daylight Saving Time in March, the offset from Hawaii to the West Coast (Pacific Time) becomes 3 hours instead of the standard 2 hours. Honolulu sees solar noon at approximately 12:30 PM HST in summer. HST is the same offset as Cook Island Time (CKT) and Tahiti Time (TAHT) in French Polynesia, allowing easy mental conversion across the central Pacific. Time-sensitive activities affected by HST include Pacific tsunami warning system coordination per NOAA NTWC, US military operations from Joint Base Pearl Harbor-Hickam, and the Mauna Kea astronomical observatories' nightly observing schedules.