Convert CST to GMT
Compare Central Standard Time and Greenwich Mean Time with a live hour-by-hour table, meeting planner, and calendar export tools.
How Conversion Works
Convert Central Standard Time to Greenwich Mean Time using the current UTC offsets: CST is UTC-6 and GMT is UTC+0. The converter applies the 6-hour difference automatically and updates for timezone rules when needed.
Hour-by-Hour Time Table
View a visual grid and hour-by-hour table showing CST alongside GMT for the full day. Export selected times with ICS download or send them to Google Calendar and Gmail.
Schedule Meetings Accurately
Find overlapping business hours between Central Standard Time and Greenwich Mean Time to plan calls and meetings. DST tracking and historical timezone changes are handled automatically using the IANA timezone database.
How to Convert CST to GMT
Looking for China Standard Time? See /time-converter/cst-china-time-zone.
Looking for Cuba Standard Time? See /time-converter/cst-cuba-time-zone.
Open the CST to GMT converter: Go to https://www.xconvert.com/time-converter/cst-to-gmt-converter when you need to line up Central Standard Time with Greenwich Mean Time for a client call, shipping update, or remote team handoff. The page opens with Central Standard Time and Greenwich Mean Time arranged on a visual comparison grid, so you can immediately see that GMT is 6 hours ahead of CST across the 24-hour timeline.
Add comparison cities if your schedule involves multiple regions: Click + Add City and search for places that commonly work alongside Central Standard Time or Greenwich Mean Time, such as Chicago or Mexico City for North American operations and London for UK-based finance, media, or legal teams. This is useful if you are coordinating a support shift across the United States and the United Kingdom, or comparing a manufacturing schedule in Mexico with a partner working on GMT.
Drag across the grid to select a meeting window: Click Select, then drag across the Central Standard Time row to highlight a range in purple, such as 9:00 to 12:00 CST, and the grid will show the matching 15:00 to 18:00 GMT window. That visual comparison makes it easy to confirm whether a morning meeting in Central Standard Time still lands inside the afternoon workday for teams using Greenwich Mean Time.
Export the selected time for sharing: After selecting a range, use the export options for ICS download, Google Calendar, Gmail, Copy to clipboard, or Share link depending on how your team works. For example, an ICS file is practical for a recurring operations review, while a Gmail draft or share link is faster when sending a one-off meeting proposal to colleagues in the United Kingdom, Ghana, or the United States.
Understanding the CST to GMT Time Difference
CST (Central Standard Time, UTC-6) is 6 hours behind GMT (Greenwich Mean Time, UTC+0), and GMT is 6 hours ahead of CST. In practical terms, 9:00 CST = 15:00 GMT, 12:00 CST = 18:00 GMT, 15:00 CST = 21:00 GMT, and 18:00 CST = 0:00 GMT on the next day. That next-day rollover matters when you schedule late-afternoon work in Central Standard Time with teams working on Greenwich Mean Time.
Central Standard Time is a standard-time abbreviation, and its daylight saving counterpart is CDT. Greenwich Mean Time is also a standard-time abbreviation, and its daylight saving counterpart is BST. Because both abbreviations can switch to daylight-saving forms during part of the year, the CST-to-GMT relationship does not stay fixed in every month; the difference changes during DST periods rather than remaining on the standard 6-hour gap year-round.
Central Standard Time is used across parts of Belize, Canada, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and the United States. Greenwich Mean Time is used in Burkina Faso, Gambia, Ghana, Guernsey, Guinea, Guinea-Bissau, Iceland, Ireland, Isle of Man, Ivory Coast, Jersey, Liberia, Mali, Mauritania, Saint Helena, Sao Tome and Principe, Senegal, Sierra Leone, Togo, and the United Kingdom. That makes this conversion especially relevant for logistics, customer support, education, and cross-Atlantic business coordination.
Best Times for Calls and Meetings Between CST and GMT
Central Standard Time and Greenwich Mean Time can overlap well for business communication when meetings are placed in the Central Standard Time morning or around midday. Using the standard conversion examples, 9:00 CST = 15:00 GMT and 12:00 CST = 18:00 GMT, which creates a practical shared window for project check-ins, account reviews, and vendor calls that need both sides online during normal office hours.
A 9:00 CST meeting works well when the Greenwich Mean Time side is starting its mid-afternoon at 15:00 GMT. A 12:00 CST meeting reaches 18:00 GMT, which is often still workable for end-of-day coordination, especially for teams handling publishing deadlines, international customer escalations, or same-day approvals between North America and the United Kingdom.
Later Central Standard Time meetings become less convenient for Greenwich Mean Time participants. For example, 15:00 CST = 21:00 GMT, which pushes the call into the evening, and 18:00 CST = 0:00 GMT the next day, which is generally unsuitable for regular business meetings. If you are planning recurring sessions, the most reliable standard-time window is usually earlier in the Central Standard Time day so the Greenwich Mean Time side stays within afternoon or early evening hours.
Frequently Asked Questions
What is the time difference between CST and GMT?
CST (Central Standard Time, UTC-6) is 6 hours behind GMT (Greenwich Mean Time, UTC+0). The reverse is also true: GMT is 6 hours ahead of CST. This means a workday that starts in the morning in Central Standard Time appears in the afternoon on Greenwich Mean Time.
When is 9 AM CST in GMT?
9:00 CST = 15:00 GMT. This is a useful conversion for scheduling transatlantic meetings because a morning start in Central Standard Time lands in the middle of the afternoon for teams using Greenwich Mean Time, making it one of the more practical options for same-day collaboration.
Does the difference between Central Standard Time and Greenwich Mean Time change during DST?
Yes. Central Standard Time uses CDT as its daylight saving counterpart, and Greenwich Mean Time uses BST as its daylight saving counterpart, so the standard 6-hour difference does not remain the same throughout every month of the year. If your meeting series runs across seasonal clock changes, review the schedule carefully because the gap can shift when one or both regions move off their standard-time abbreviations.
What is the best meeting time between CST and GMT?
The most practical standard-time meeting window is usually the Central Standard Time morning through midday. The examples show why: 9:00 CST = 15:00 GMT and 12:00 CST = 18:00 GMT, which keeps the meeting inside normal business hours for CST and within the afternoon or early evening for GMT. By contrast, 15:00 CST = 21:00 GMT is already late for GMT participants.
Is CST Central Standard Time or China Standard Time?
On this page, CST means Central Standard Time (UTC-6). CST can also mean China Standard Time (UTC+8), which is a different time zone entirely; for that meaning, use /time-converter/cst-china-time-zone. CST can also refer to Cuba Standard Time (UTC-5) on its separate page at /time-converter/cst-cuba-time-zone.
What time is 12 PM CST in GMT?
12:00 CST = 18:00 GMT. This conversion is especially useful for booking midday calls from Central Standard Time with partners in GMT-based locations such as the United Kingdom, Ghana, or Ireland, because it reaches them near the end of the business day rather than after hours.
What time is 6 PM CST in GMT?
18:00 CST = 0:00 GMT on the next day. The date change is important: an evening event, deadline, or handoff in Central Standard Time becomes midnight in Greenwich Mean Time, so teams should confirm not just the hour but also the calendar day when sharing schedules.