What is the time difference between UTC and HST?

Hawaii Standard Time (HST) is 10 hours behind Coordinated Universal Time (UTC). UTC uses a UTC offset of UTC, while HST uses UTC-10. For example, when it's 9:00 AM in UTC, it's 11:00 PM in HST. This difference remains constant year-round since neither timezone observes daylight saving time. Use the conversion table above to see the exact time for each hour of the day.

How do I convert UTC to HST?

To convert UTC to HST, subtract 10 hours from the UTC time. For example, 9:00 AM UTC is 11:00 PM HST, and 5:00 PM UTC is 7:00 AM HST. Since neither timezone observes DST, this conversion stays the same all year. You can also use the interactive converter above for quick, accurate results.

What time is it in HST when it's noon in UTC?

When it's 12:00 PM (noon) in UTC, it's 2:00 AM in HST. This is because HST is 10 hours behind UTC. Similarly, when it's 6:00 PM in UTC, it's 8:00 AM in HST. This relationship is constant throughout the year. The color-coded conversion table above shows every hour mapped between both timezones.

How many hours behind is HST from UTC?

HST is 10 hours behind UTC. This means when it's 9:00 AM in UTC, it's 11:00 PM in HST, and when it's midnight in UTC, it's 2:00 PM in HST. This offset is constant throughout the year since neither timezone uses daylight saving time. The conversion table above provides a complete hour-by-hour mapping.

Is HST ahead or behind UTC?

HST is behind UTC by 10 hours. Clocks in HST show an earlier time than UTC, meaning the day starts later in HST relative to UTC. For example, when it's noon in UTC, it's still 2:00 AM in HST. This difference stays the same year-round.

Does UTC observe daylight saving time?

No, Coordinated Universal Time does not observe daylight saving time. The UTC offset of UTC remains the same year-round, which simplifies time conversions. Regions using UTC keep their clocks unchanged regardless of the season.

Does HST observe daylight saving time?

No, Hawaii Standard Time does not observe daylight saving time. The UTC offset of UTC-10 remains the same year-round, making time conversions to HST more predictable. Countries and regions in this timezone keep their clocks unchanged regardless of the season.

What is the best time to call from UTC to HST?

The best time for a call between UTC and HST is during overlapping business hours (9 AM – 5 PM) in both timezones. To reach someone in HST during their work day, call between 7:00 PM and 3:00 AM your UTC time. Avoid calling too early or late, as the 10 hours difference means your evening could be their early morning. Check the color-coded conversion table above — green hours indicate business hours in both zones, making it easy to find the ideal time.

Do UTC and HST ever have the same time?

No, UTC and HST are always 10 hours apart and never display the same clock time simultaneously. Neither timezone observes DST, so the difference is constant year-round with no seasonal variation. The 10 hours offset is determined by their fixed positions relative to the Prime Meridian (UTC). You can always rely on this consistent difference when planning across these timezones.

UTC to HST Converter

Convert Coordinated Universal Time to Hawaii Standard Time. See the hour-by-hour conversion table below.

Timezone Details

UTC

2:31 AM

Friday, April 3, 2026

UTC (UTC+00:00)

Hawaii Standard Time

4:31 PM

Thursday, April 2, 2026

HST (UTC-10:00)

Difference: -10 hours

HST DST: No

24-Hour Overview

UTC — 24-hour overview

12a12a

3a3a

6a6a

9a9a

10a

11a

12p12p

3p3p

6p6p

9p9p

10p

11p

NightMorningBusinessEvening

HST — 24-hour overview

2p2p

5p5p

8p8p

10p

11p11p

12a

2a2a

5a5a

8a8a

10a

11a11a

12p

NightMorningBusinessEvening

Frequently Asked Questions

Related Conversions

HST to UTC

Cities in These Timezones

HST Cities

Honolulu

More Tools

Compare UTC & HST Plan a Meeting (UTC & HST)See on Map

Learn More

How Time Zones Work Understanding DST Timezone Abbreviations

External Resources

Coordinated Universal Time on Wikipedia Hawaii Standard Time on Wikipedia IANA Time Zone Database