Does it handle Daylight Saving Time?

Yes, the tool automatically adjusts for Daylight Saving Time based on the specific date you select, ensuring accurate conversions year-round.

Can I add multiple cities?

Yes, you can add as many cities as you need to the dashboard to compare times across your entire global network simultaneously.

Chicago to Colombo

+10h 30m

Chicago

CDTSOURCE

USA · UTC-05:00☀ DST active

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Colombo

IST

Sri Lanka · UTC+05:30

HH10

MM30

22:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Chicago

Colombo

12:00 AM

10:30 AM

2:00 AM

12:30 PM

4:00 AM

2:30 PM

6:00 AM

4:30 PM

8:00 AM

6:30 PM

10:00 AM

8:30 PM

12:00 PM

10:30 PM

2:00 PM

12:30 AM+1

4:00 PM

2:30 AM+1

6:00 PM

4:30 AM+1

8:00 PM

6:30 AM+1

10:00 PM

8:30 AM+1

Green rows indicate typical business hours (9 AM - 5 PM)

CDT and IST on the World Map

The map below highlights the CDT (Central Standard Time) and IST (India Standard Time) timezone regions across the globe.

CDT Zone

→

IST Zone

Explore all world timezones interactively →

CST – Central Standard Time

UTC-06:00

Central Standard Time (CST) is the time zone for the central United States, Canada, and Mexico, 6 hours behind UTC.

Countries in CST

United States (Central)Canada (Manitoba, Saskatchewan)MexicoGuatemalaHondurasEl SalvadorCosta RicaNicaraguaBelize

Major Cities in CST

ChicagoHoustonDallasSan AntonioMexico CityAustinWinnipegMemphisMilwaukeeNashvilleKansas CityNew OrleansMinneapolisGuatemala City

Key Facts about CST

•CST covers 20 US states fully or partially.
•Chicago and Houston are the two largest cities in the Central Time Zone.
•Mexico City, one of the world's most populous cities, operates on CST.
•CST is 1 hour behind EST and 2 hours ahead of PST.

Daylight Saving:Yes – switches to CDT

Learn more about CST on Wikipedia

IST – India Standard Time

UTC+05:30

India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.

Countries in IST

IndiaSri Lanka

Major Cities in IST

MumbaiDelhiBangaloreKolkataChennaiHyderabadPuneAhmedabadColomboJaipurLucknowSurat

Key Facts about IST

•India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
•India uses a single time zone despite spanning 30° of longitude.
•IST is one of only a handful of time zones with a 30-minute offset.
•IST is the most populous single time zone in the world with over 1.4 billion people.
•The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.

Daylight Saving:No – UTC+05:30 year-round

Learn more about IST on Wikipedia

About Chicago

Wikipedia

Chicago operates on Central Time (CST/CDT), 1 hour behind New York. Home to CME and CBOE, Chicago is a global center for derivatives trading.

Population:2.7 million

Metro:9.5 million

Business Hours:8:00 AM - 5:00 PM CST

Currency:USD ($)

Stock Exchange:CME (Chicago Mercantile Exchange), CBOE

Key Landmarks

Willis TowerMillennium ParkCloud Gate (The Bean)Navy PierArt Institute of Chicago

Did You Know?

The Chicago Board of Trade is the world's oldest futures and options exchange.

Learn more about CDT timezone →

About Colombo

Wikipedia

Colombo operates on Sri Lanka Time (SLST), UTC+5:30. Sharing India's timezone, Colombo is a key South Asian trade and tourism hub.

Population:752,000

Metro:5.6 million

Business Hours:9:00 AM - 5:00 PM IST

Currency:LKR (Rs)

Stock Exchange:CSE (Colombo Stock Exchange)

Key Landmarks

Galle Face GreenGangaramaya TempleColombo Lotus TowerIndependence SquareDutch Hospital

Did You Know?

Sri Lanka Standard Time (SLST) uses UTC+5:30, same offset as India.

Learn more about IST timezone →

Everything You Need to Know About Chicago and Colombo Time

Chicago runs on Central Daylight Time (CDT) at UTC-05:00, currently observing daylight saving time. Colombo runs on India Standard Time (IST) at UTC+05:30. That puts Chicago 10 hours 30 minutes ahead of Colombo — a difference of +10h 30m at the current offsets.

In practice, when it is 9:00 AM in Chicago it is 7:30 PM in Colombo. Midnight in Chicago is 10:30 AM in Colombo.Chicago observes daylight saving time while Colombo does not, so the gap narrows or widens by an hour part of the year.

Chicago to Colombo time conversion table

Chicago (CDT)	Colombo (IST)	Day
12:00 AM	10:30 AM	same day
6:00 AM	4:30 PM	same day
7:00 AM	5:30 PM	same day
8:00 AM	6:30 PM	same day
9:00 AM	7:30 PM	same day
12:00 PM	10:30 PM	same day
3:00 PM	1:30 AM	next day
5:00 PM	3:30 AM	next day
6:00 PM	4:30 AM	next day
9:00 PM	7:30 AM	next day

Why people convert Chicago to Colombo time

Scheduling a call from Chicago to Colombo: a 10:00 AM start in Chicago lands at 8:30 PM in Colombo, so you can confirm the slot without doing the arithmetic yourself.
Handling a +10h 30m gap: Chicago and Colombo have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in Colombo is 7:30 PM in Chicago.
Booking travel or deliveries: tracking Colombo local time against Chicago keeps pickup windows and arrival estimates honest across the +10h 30m offset.

Always state the zone abbreviation, not just the hour. "3:00 PM CDT" is unambiguous; "3 PM" across a +10h 30m gap is not.
With a +10h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week Chicago takes the early slot, the next week Colombo does.
Chicago: Clocks fall back on Sun, Nov 1, 2026. Re-check this page after that date because the offset changes and so does the +10h 30m gap.

About CST (Central Standard Time)

Central Standard Time (CST) covers the central region of North America. It is the second most populous time zone in the US, including major cities like Chicago, Houston, and Dallas. CST is also used in Mexico City and much of Central America including Guatemala, Honduras, El Salvador, and Costa Rica. During summer, most of the US and Canada switch to Central Daylight Time (CDT, UTC-05:00), while Mexico and Central American countries generally remain on CST.

About IST (India Standard Time)

India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.

Best time to call between Chicago and Colombo

With a +10h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. Colombo opens at 9:00 AM IST, which is 7:30 PM in Chicago, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Chicago and Colombo have no shared working hours because of the +10h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.

Chicago is 10 hours 30 minutes ahead of Colombo (CDT UTC-05:00 → IST UTC+05:30). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

Chicago

☀ Currently in DST

Standard: UTC-06:00 · DST: UTC-05:00

Clocks fall back on Sun, Nov 1, 2026

Colombo

Does not observe DST

Learn More About Time

Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:

⏳

History of Timekeeping

From sundials to atomic clocks - 5000 years of measuring time

🌍

How Time Zones Work

UTC, offsets, and why zones don't follow straight lines

☀️

Daylight Saving Time

DST dates, which countries observe it, and the ongoing debate

Frequently Asked Questions

What is the time difference between Chicago and Colombo?

Chicago (CDT, UTC-05:00) is 10 hours 30 minutes ahead of Colombo (IST, UTC+05:30). The gap is currently +10h 30m.

How do I convert Chicago time to Colombo time?

Add +10h 30m to Chicago local time. For example, 9:00 AM in Chicago is 7:30 PM in Colombo.

What time is it in Colombo right now?

Colombo uses IST at UTC+05:30. Use the live converter at the top of this page — it updates in real time and already accounts for the +10h 30m offset from Chicago.

What is the best time to call Colombo from Chicago?

There is no shared working-hours window because of the +10h 30m gap. The closest option is 1:00 PM in Chicago, which is 11:30 PM in Colombo.

Which is ahead, Chicago or Colombo?

Chicago is 10 hours 30 minutes ahead of Colombo. When it is 12:00 PM in Chicago it is 10:30 PM in Colombo.

Do Chicago and Colombo use different time zones?

Chicago (USA) uses CDT at UTC-05:00, while Colombo (Sri Lanka) uses IST at UTC+05:30. The IANA identifiers are America/Chicago and Asia/Colombo.

Does daylight saving time affect the Chicago–Colombo difference?

Yes at the moment: Chicago is on daylight saving time and Colombo is not, so the +10h 30m gap shifts by an hour when exactly one of them changes clocks.

Which other cities share Chicago's time zone?

CDT also covers Chicago, Houston, Dallas, San Antonio, Mexico City, Austin, Winnipeg, Memphis and 6 more.

Which countries use CDT, Chicago's zone?

CDT is used in United States (Central), Canada (Manitoba, Saskatchewan), Mexico, Guatemala, Honduras, El Salvador, Costa Rica, Nicaragua and 1 more.

Is there a day difference between Chicago and Colombo?

Not normally. The +10h 30m gap only pushes the date over for late-evening times.

What is the time difference between Chicago and Colombo?

Colombo is +10h 30m from Chicago.

What timezone is Chicago in?

Chicago operates on Central Time (CST/CDT), 1 hour behind New York. Home to CME and CBOE, Chicago is a global center for derivatives trading.

What timezone is Colombo in?

Colombo operates on Sri Lanka Time (SLST), UTC+5:30. Sharing India's timezone, Colombo is a key South Asian trade and tourism hub.

What are the business hours in Chicago?

Standard business hours in Chicago are 8:00 AM - 5:00 PM CST.

What are the business hours in Colombo?

Standard business hours in Colombo are 9:00 AM - 5:00 PM IST.

What is the best time to schedule a call between Chicago and Colombo?

The best overlap for a call is when both cities are in business hours. Chicago works 8:00 AM - 5:00 PM CST and Colombo works 9:00 AM - 5:00 PM IST (+10h 30m difference). Try scheduling during the overlapping window for maximum convenience.

What currencies are used in Chicago and Colombo?

Chicago uses USD ($) while Colombo uses LKR (Rs). Check current exchange rates when planning travel or business between these cities.

How do Chicago and Colombo compare in size?

Chicago has a population of approximately 2.7 million (metro: 9.5 million), while Colombo has approximately 752,000 (metro: 5.6 million).

What are the major landmarks in Chicago and Colombo?

Chicago is known for Willis Tower, Millennium Park, Cloud Gate (The Bean). Colombo is famous for Galle Face Green, Gangaramaya Temple, Colombo Lotus Tower.

Do Chicago and Colombo have stock exchanges?

Yes. Chicago has the CME (Chicago Mercantile Exchange), CBOE and Colombo has the CSE (Colombo Stock Exchange). The +10h 30m time difference affects trading hour overlaps between these exchanges.