HST to CDT Converter
Convert time between Hawaii Standard Time (HST) and Central Daylight Time (CDT)
Hawaii Standard Time (HST)
Central Daylight Time (CDT)
Time Difference
Central Daylight Time (CDT) is 0 hours ahead of Hawaii Standard Time (HST)
Select Date
Select Time
Quick Reference
| HST | CDT |
|---|---|
| 16:00 | 20:00 |
| 18:00 | 22:00 |
| 20:00 | 00:00 |
| 22:00 | 02:00 |
| 00:00 | 04:00 |
| 02:00 | 06:00 |
| 04:00 | 08:00 |
| 06:00 | 10:00 |
| 08:00 | 12:00 |
| 10:00 | 14:00 |
| 12:00 | 16:00 |
| 14:00 | 18:00 |
Top 10 Most Common Time Zones
| Abbreviation | Full Name | UTC Offset | Typical Use |
|---|---|---|---|
| UTC | Coordinated Universal Time | UTC ±0 | Global reference standard (servers, logs, APIs) |
| EST / EDT | Eastern (US) Time | UTC −5 / −4 | New York, Toronto — North American business hub |
| CST / CDT | Central (US) Time | UTC −6 / −5 | Chicago, Dallas — US central business region |
| PST / PDT | Pacific (US) Time | UTC −8 / −7 | San Francisco, Los Angeles — tech industry standard |
| GMT / BST | Greenwich Mean / British Summer Time | UTC 0 / +1 | UK, used globally as a reference with UTC |
| CET / CEST | Central European (Summer) Time | UTC +1 / +2 | Paris, Berlin, Amsterdam — EU business core |
| IST | India Standard Time | UTC +5:30 | India — major IT & outsourcing region |
| CST | China Standard Time | UTC +8 | Beijing, Shanghai — East Asia business hub |
| JST | Japan Standard Time | UTC +9 | Tokyo — finance & tech hub |
| AEST / AEDT | Australian Eastern (Daylight) Time | UTC +10 / +11 | Sydney, Melbourne — APAC regional business |
Why Time Zone Abbreviations Are Ambiguous
Unlike standardized identifiers (like America/New_York or Europe/London from the IANA tz database), abbreviations such as "CST" or "IST" are not globally unique. They can refer to different time zones depending on context — country, region, or even time of year (due to daylight saving time).
Common Ambiguous Time Zone Abbreviations
| Abbrev. | Common Meaning(s) | UTC Offset | Region(s) |
|---|---|---|---|
| CST | Central Standard Time / China Standard Time / Cuba Standard Time | UTC−6 / UTC+8 / UTC−5 | North America, China, Cuba |
| IST | Indian Standard Time / Irish Standard Time / Israel Standard Time | UTC+5:30 / UTC+1 / UTC+2 | India, Ireland, Israel |
| AST | Atlantic Standard Time / Arabia Standard Time | UTC−4 / UTC+3 | Caribbean, Canada, Middle East |
| PST | Pacific Standard Time / Philippine Standard Time | UTC−8 / UTC+8 | North America, Philippines |
| EST | Eastern Standard Time (North America / Australia) | UTC−5 / UTC+10 | North America, Australia |
✅ Best Practice
To avoid ambiguity, always:
- Use IANA tz identifiers — e.g.,
America/New_Yorkinstead of "EST" - Specify UTC offset explicitly — e.g.,
UTC−5when abbreviations must be used - Include the full timezone name — e.g., "Eastern Standard Time (EST)" with UTC offset
Related Time Zone Conversions
About HST to CDT Time Conversion
Converting time between Hawaii Standard Time (HST) and Central Daylight Time (CDT) is important for coordinating between Hawaii and the US Central region during daylight saving time. HST is UTC-10, while CDT is UTC-5, making CDT 5 hours ahead of HST. Hawaii does not observe daylight saving time, but the Central US does, adding complexity to the conversion.
This conversion is vital for business operations between Hawaii and the Midwest/Central US, including cities like Chicago, Dallas, Houston, and Kansas City. Understanding this time difference is crucial for scheduling meetings, managing operations, and coordinating activities between Hawaii and the central United States, especially during the March-November daylight saving period.
Common Use Cases for HST to CDT Conversion
Business & Work
- Scheduling calls between Hawaii offices and Central US headquarters during daylight saving time
- Coordinating business operations between Hawaii and Midwest regions
- Managing customer service across Hawaii and Central time zones
Personal & Travel
- Scheduling video calls with family and friends in the Midwest
- Planning travel between Hawaii and Central US cities
- Coordinating vacation time across regions during spring and summer months
Time Zone Information
Hawaii Standard Time (HST)
- UTC Offset: UTC-10
- IANA Timezone: Pacific/Honolulu
- Daylight Saving: No daylight saving time observed
- Major Cities: Honolulu, Hilo, Maui, Kauai, Big Island
- Coverage: State of Hawaii
Central Daylight Time (CDT)
- UTC Offset: UTC-5 (UTC-6 during CST)
- IANA Timezone: America/Chicago
- Daylight Saving: Second Sunday in March to First Sunday in November
- Major Cities: Chicago, Dallas, Houston, Austin, San Antonio, Kansas City
- Coverage: Central United States and parts of Canada and Mexico
Quick Reference: HST to CDT
Remember: CDT is always 5 hours ahead of HST during daylight saving time (March-November). Outside this period, CST is 4 hours ahead of HST
Frequently Asked Questions
What is the time difference between HST and CDT?
Hawaii Standard Time (HST) is UTC-10, while Central Daylight Time (CDT) is UTC-5. CDT is 5 hours ahead of HST. This means when it's 8:00 AM in HST, it's 1:00 PM the same day in CDT.
Does Hawaii observe daylight saving time?
No, Hawaii does not observe daylight saving time. Hawaii Standard Time (HST) remains UTC-10 year-round. However, the Central region observes daylight saving time, transitioning from CST (UTC-6) to CDT (UTC-5). This means the time difference varies between 4 hours (when CST is active, November-March) and 5 hours (when CDT is active, March-November).
How does HST to CDT differ from HST to CST?
CDT (Central Daylight Time) is 1 hour ahead of CST (Central Standard Time). When CDT is active (March-November), the difference between HST and CDT is 5 hours. When CST is active (November-March), the difference between HST and CST is 4 hours. CDT is used during daylight saving time in the Central region.
What major cities are in HST and CDT timezones?
HST covers Hawaii cities including Honolulu, Hilo, Maui, Kauai, and the Big Island. CDT covers major Central region cities like Chicago, Dallas, Houston, Austin, Memphis, and New Orleans. These regions represent Hawaii and the American heartland during daylight saving time (March-November).
How do I convert HST to CDT manually?
To convert from HST to CDT, add 5 hours to the HST time. For example, if it's 9:00 AM HST, it would be 2:00 PM CDT the same day. Remember this conversion is only valid during daylight saving time (March-November). When CST is active (November-March), add only 4 hours instead.
What should I know about scheduling across HST and CDT?
Hawaii is 5 hours behind the Central region during CDT, making coordination challenging but possible. Morning CDT times (9-11 AM) correspond to early morning HST times (4-6 AM), and late afternoon CDT (3-5 PM) corresponds to late morning HST (10 AM-12 PM). For regular business coordination, early morning CDT calls (7-9 AM) work well with Hawaii (2-4 AM HST for early risers, or 2-4 PM HST for evening workers).
Pro Tips
- • CDT is always 5 hours ahead of HST during daylight saving time (March-November). Outside this period, CST is 4 hours ahead.
- • Hawaii does not observe daylight saving time, so HST is consistent year-round while CDT changes twice annually.
- • Late afternoon CDT (3-5 PM) aligns well with late morning/early afternoon HST (10 AM-12 PM) for mid-day meetings.
- • Morning hours (7-9 AM CDT = 2-4 AM HST) work for early risers in Hawaii coordinating with Central region business hours.
- • Use 24-hour time format when communicating across HST-CDT to eliminate AM/PM confusion, especially around morning/evening transitions.
- • Tourism, hospitality, and business operations between Hawaii and the Central US can coordinate during seasonal peaks and overlapping hours.