Military Communications
Military Date-Time Group
The Date-Time Group (DTG) is the military standard for expressing a precise moment in time within a message or document. A single DTG encodes the day, hour, minute, time zone, month, and year into a compact string — no calendar lookup required.
The Format
This DTG reads: 6th day of January 2026, at 1830 hours Zulu time. Every element of the timestamp is present, in a fixed-position format that any trained military communicator can parse instantly.
Component Breakdown
Anatomy of a DTG
| Position | Component | Format | Example | Notes |
|---|---|---|---|---|
| 1–2 | Day | DD | 06 | Two digits, zero-padded. 01–31. |
| 3–4 | Hour | HH | 18 | Military time, 0000–2359. |
| 5–6 | Minute | mm | 30 | Two digits, 00–59. |
| 7 | Time Zone | Z | Z | NATO time zone letter. Z = UTC. See full zone list. |
| 8–10 | Month | MMM | JAN | Three-letter abbreviation, uppercase. |
| 11–12 | Year | YY | 26 | Two-digit year. Context prevents ambiguity in military records. |
Full Format: DDHHmmZMMMYY
The DTG format is sometimes written as DDHHmmZMMMYY in doctrinal references, where lowercase letters indicate numeric fields and uppercase letters indicate alphabetic fields. The time zone letter (Z in the format string) is replaced by the actual NATO zone designator for the time being expressed.
Note that there are no separators — no slashes, colons, or spaces — between components. The DTG is always written as a continuous string, which makes it compact for message traffic and unambiguous in parsing.
Examples
Reading Real DTGs
6 January 2026, 18:30 UTC (Zulu)
Day 06, hour 18, minute 30, Zulu time zone, January, year 2026. Standard format for a NATO headquarters message transmitted at 6:30 PM UTC.
14 April 2026, 12:00 Lima time (UTC−5, US Eastern Standard)
Day 14, noon, Lima zone (UTC−5), April, 2026. Lima is used in Pentagon and East Coast US operations when referencing local time. Noon here is 1700Z.
1 January 2026, 00:01 UTC — one minute into New Year
The use of 0001 rather than 0000 is a deliberate choice when the author wants to unambiguously indicate "the very start of the day, clearly past midnight." Common in operations orders that take effect at the open of a specific date.
15 June 2025, 23:45 Bravo time (UTC+2)
Bravo zone covers Central European Summer Time (CEST) and similar UTC+2 regions. 23:45B = 21:45Z. Often seen in European theater operations messages.
20 November 2025, 06:00 India time (UTC+9)
India zone (UTC+9) covers Japan Standard Time (JST) and Korea Standard Time (KST). Used in Pacific Command (PACOM) message traffic. 0600I = 2100Z the previous day.
Operational Use
When and Where DTG Is Used
The DTG appears in virtually every formal military document that references a specific time. Its compact format and built-in time zone designation make it the only practical choice for multi-national, multi-theater operations.
Operations Orders (OPORDs)
Every timed event in an operations order — H-hour, phase lines, report times, supply runs — is expressed as a DTG. The format ensures that units operating across time zones receive unambiguous timing instructions.
SITREPs and Message Traffic
Situation reports (SITREPs) include a DTG in the header indicating when the report was generated. Message traffic using USMTF (US Message Text Format) or NATO STANAG 2014 requires a DTG header on every message.
Logs and Records
Unit journals, radio logs, and personnel records use DTGs for all entries. A DTG in a log entry provides a legally defensible, unambiguous timestamp that can be verified against any other DTG in the same theater.
Intelligence Reports (INTREPs)
Intelligence reports require precise "time of information" and "time of report" fields, both expressed as DTGs. When tracking adversary movements, a one-hour error in a timestamp can invalidate an entire intelligence picture.
Air Mission Briefs
Takeoff times, tanker rendezvous windows, target time-over-target (TOT), and recovery times are all expressed as DTGs in aviation mission briefs, coordinating across aircraft from different countries and time zones.
Fragmentary Orders (FRAGOs)
Changes to operations orders are issued as FRAGOs, each carrying a DTG that establishes when the change takes effect. Without a precise DTG, a FRAGO could be applied at the wrong time, with potentially fatal consequences.
Standards
NATO STANAG Requirements
The DTG format is codified in NATO Standardization Agreement (STANAG) 2014, which establishes the format for military messages and documents used across all NATO member nations. STANAG 2014 requires that all time references in message traffic use the DTG format, ensuring that a message originated by a French unit and received by a US unit carries a timestamp that both can interpret identically.
Under STANAG 2014, the DTG is required in the message header and may appear multiple times within the body of a message when multiple events or reporting periods are referenced. The standard specifies that Zulu (UTC) time is the preferred time zone for all NATO coordinated operations, though local time zone designators may be used when the local operational context requires it.
Time zone discipline: Mixed-zone DTGs in the same document are a known source of operational errors. Best practice is to establish a single time zone reference (usually Zulu) for all DTGs within an operation, and include local time only as a parenthetical where needed for clarity.
Voice Procedure
How to Speak a DTG Aloud
When reading a DTG aloud over radio or in a briefing, each component is spoken separately. Numbers are spoken as individual digits or as grouped numbers, and the time zone letter is spoken using its NATO phonetic name.
Spoken as: "Zero six, eighteen thirty, Zulu, January, two six"
Spoken as: "One four, twelve hundred, Lima, April, two six"
The year is typically spoken as two separate digits ("two six" for 26) rather than as the full year ("twenty-twenty-six") to maintain concision on radio nets. Context within a document or operation eliminates any ambiguity about the century.