AST CSTTime Converter
AST (UTC−4) is currently 2 hours ahead of CST (UTC−6). Compare live clocks, convert any hour, and find times to meet.
Best time to meet between AST and CST
Best meeting times:
AST: 11:00 AM – 6:00 PM
CST: 9:00 AM – 4:00 PM
Quick answer
When it's in AST, it's the same day in CST.
AST runs 2 hours ahead of CST. Both sides keep standard office hours with a real 9–6 overlap: the highlighted window above works for everyone.
- Time difference
- −2h 00m
- AST
- UTC−4
- CST
- UTC−6
- Best call window
- 11:00 AM AST
AST to CST conversion table
The next 12 hours in AST and the matching local time in CST. The current hour is highlighted; drag the converter's slider and the table follows.
| AST | CST |
|---|---|
| NOW Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Thu, Aug 6 |
Fri, Aug 7 |
Thu, Aug 6 |
Fri, Aug 7 |
Thu, Aug 6 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
Fri, Aug 7 |
This time difference never changes
Neither side observes daylight saving against the other, so the gap stays constant all year. Regions on AST switch to ADT (UTC−3) during daylight saving time. Regions on CST switch to CDT (UTC−5) during daylight saving time. This page always shows the live, DST-aware difference.
Related time zone conversions
Jump straight to another pair: every combination is a live tool, not an article.
From AST
To CST
One source of truth, for you and your AI
This page exposes the same answer as structured data, so when you ask an assistant "what's 9am AST time in CST?", it can cite the exact, DST-aware result, not a stale blog post.
- Schema.org JSON-LD on every converter page
- A machine-readable facts island with time zone identifiers and every possible offset
- Live times in <time datetime> elements with explicit UTC offsets
{
"pair": "AST → CST",
"url": "https://worldclock.pro/en/convert/ast-to-cst",
"from": {
"name": "AST",
"type": "timezone",
"abbreviation": "AST",
"daylightAbbreviation": "ADT",
"iana": "America/Halifax",
"standardUtcOffset": "-04:00",
"daylightUtcOffset": "-03:00",
"referenceCity": "Halifax"
},
"to": {
"name": "CST",
"type": "timezone",
"abbreviation": "CST",
"daylightAbbreviation": "CDT",
"iana": "America/Chicago",
"standardUtcOffset": "-06:00",
"daylightUtcOffset": "-05:00",
"referenceCity": "Chicago"
},
"currentDifferenceMinutes": -120,
"possibleDifferencesMinutes": [
-120
],
"note": "The difference is constant year-round."
}
Frequently asked questions
What is the time difference between AST and CST?
AST is currently 2 hours ahead of CST. AST is on AST (UTC−4) and CST is on CST (UTC−6). The difference can change when either side starts or ends daylight saving time.
Is CST ahead of or behind AST?
CST is currently 2 hours behind AST.
When it is 9:00 AM in AST, what time is it in CST?
When it is 9:00 AM on a Thursday in AST, it is 7:00 AM in CST.
Do AST and CST observe daylight saving time?
Regions on AST switch to ADT (UTC−3) during daylight saving time. Regions on CST switch to CDT (UTC−5) during daylight saving time.
How do I convert AST time to CST time?
Subtract 2 hours from any time in AST to get the time in CST. This page's converter and 24-hour table do it automatically and stay correct through daylight-saving changes.
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