World Codes Cheat Sheet

Quick reference for reading a world’s Universal World Profile (UWP), trade codes, and map symbols (Mongoose Traveller 2e Core Rulebook, 2022 Update — sourced via the Core Rulebook in NotebookLM). See also the Skill Check Cheat Sheet, Combat Cheat Sheet and Spaceship Operations Cheat Sheet. For worked-up local examples see Flammarion, Walston and 567-908.


The UWP at a Glance

A world’s profile is eight characters plus a hyphen, e.g. A623514-B:

PositionAttributeThis example
1StarportA — excellent
2Size6 — ~9,600 km
3Atmosphere2 — very thin, tainted
4Hydrographics3 — ~30% water
5Population5 — hundreds of thousands
6Government1 — company/corporation
7Law Level4 — moderate
(separator)
8Tech LevelB — TL 11, early stellar

Any digit of 10 or more is written in hex: A=10, B=11, C=12 … F=15. The hyphen is only a separator before Tech Level.

1 · Starport

CodeQualityFuelFacilitiesTypical berthing
AExcellentRefinedShipyard (all ships incl. starships), full repairCr1,000
BGoodRefinedShipyard (spacecraft, not starships), full repairCr500
CRoutineUnrefinedSome repair, small-craft constructionCr100
DPoorUnrefinedLimited repairCr10
EFrontierNoneNone — just a landing padCr0
XNoneNoneNone; usually a Red ZoneCr0

2 · Size (diameter & gravity)

CodeDiameterGravity
0<1,000 km (asteroid / orbital)negligible
11,600 km0.05 G
23,200 km0.15 G
34,800 km0.25 G
46,400 km0.35 G
58,000 km0.45 G
69,600 km0.70 G
711,200 km0.90 G
812,800 km1.0 G
914,400 km1.25 G
A16,000 km1.40 G

3 · Atmosphere (and gear needed outdoors)

CodeTypeGear to breathe
0None (vacuum)Vacc suit
1TraceVacc suit
2Very Thin, TaintedRespirator + Filter
3Very ThinRespirator
4Thin, TaintedFilter mask
5ThinNone
6StandardNone
7Standard, TaintedFilter mask
8DenseNone
9Dense, TaintedFilter mask
AExoticAir supply
BCorrosiveVacc suit (hostile)
CInsidiousHostile-environment suit
DVery DenseNone — but only at high elevations
ELowNone (very low pressure)
FUnusualVaries

Tainted = breathable pressure but a contaminant (dust, spores, gas) → filter. Thin/Very thin = pressure too low → respirator. A world that is both needs both (see Flammarion, atmo 2).

4 · Hydrographics (surface water)

Code% coveredCode% covered
00–5% (desert)656–65%
16–15%766–75%
216–25%876–85%
326–35%986–95%
436–45%A96–100% (water world)
546–55%

5 · Population

CodeInhabitantsCodeInhabitants
0None7Tens of millions
1Few (tens)8Hundreds of millions
2Hundreds9Billions
3ThousandsATens of billions
4Tens of thousandsBHundreds of billions
5Hundreds of thousandsCTrillions
6Millions

6 · Government

CodeTypeCodeType
0None / Anarchy8Civil Service Bureaucracy
1Company / Corporation9Impersonal Bureaucracy
2Participating DemocracyACharismatic Dictator
3Self-Perpetuating OligarchyBNon-Charismatic Leader
4Representative DemocracyCCharismatic Oligarchy
5Feudal TechnocracyDReligious Dictatorship
6Captive Government / ColonyEReligious Autocracy
7BalkanisationFTotalitarian Oligarchy

7 · Law Level (what gets you arrested)

CodeWeapons restricted (cumulative)
0No restrictions
1Poison gas, explosives, undetectable weapons, WMD
2Portable energy weapons (lasers)
3Military weapons (machine guns, automatic rifles)
4Light assault weapons, submachine guns
5Personal concealable weapons
6All firearms except shotguns & stunners; carrying restricted
7Shotguns
8Bladed weapons & stunners; open display restricted
9Any weapon outside the home
A–FEscalating: all weapons suppressed, then movement & contact controlled

Restrictions are cumulative — at Law 8 everything from Law 1–7 is also banned. Armour bans rise roughly in parallel (Battle Dress first at Law 1, then combat armour, flak, etc.).

8 · Tech Level (hex)

CodeTLEra / capability
00Primitive (stone age)
11Bronze / Iron age
22Renaissance, printing
331700s, basic science
44Industrial Revolution
55Mass production, radio (~1900s)
66Nuclear power, early computers
77Early space, orbital flight (~1970s)
88Pre-Stellar — fusion, in-system travel
99Early Stellar — first jump drive (J-1)
A10J-2, fusion+, true robots
B11J-2 (better), first AIs
C12J-3, advanced
D13J-4, holographics
E14J-5, well-developed AIs
F15J-6 — Imperial maximum

Trade Codes

Letters after the UWP flag a world’s economic role (and what buys/sells well there). A world can carry several.

CodeNameUWP requirement
AgAgriculturalAtmo 4–9, Hydro 4–8, Pop 5–7
NaNon-AgriculturalAtmo 0–3, Hydro 0–3, Pop 6+
InIndustrialAtmo 0/1/2/4/7/9/A/B/C, Pop 9+
NiNon-IndustrialPop 4–6
HiHigh PopulationPop 9+
LoLow PopulationPop 1–3
RiRichAtmo 6 or 8, Pop 6–8, Gov 4–9
PoPoorAtmo 2–5, Hydro 0–3
HtHigh TechTL 12+
LtLow TechPop 1+, TL 5 or less
AsAsteroidSize 0, Atmo 0, Hydro 0
DeDesertAtmo 2–9, Hydro 0
FlFluid OceansAtmo A+, Hydro 1+
GaGardenSize 6–8, Atmo 5/6/8, Hydro 5–7
IcIce-CappedAtmo 0–1, Hydro 1+
VaVacuumAtmo 0
WaWater WorldHydro A, Atmo 3–9 or D
BaBarrenPop 0, Gov 0, Law 0

Ag/Na, Hi/Lo and Ri/Po are opposite pairs — a world can carry at most one code from each pair.

Map Symbols & Extra Codes

  • Travel Zone (colour of the system’s hex):
    • Green / unmarked — normal, open travel.
    • Amber — caution: dangerous law, instability, or environment. Travellers advised to take care.
    • Red — interdicted: entry forbidden by Imperial authority or extreme hazard.
  • Bases (letters by the system): N Naval base · S Scout base · D Depot · W Way station.
  • PBG (3-digit code): Population multiplier (1–9, ×the population magnitude) · Belts (planetoid belts in system) · Gas giants (number in system — matters for wilderness refuelling).

Worked Examples (local worlds)

WorldUWPReads as
FlammarionA623514-BA-grade port; tiny low-G world; very thin tainted air (respirator+filter); 30% water; ~100k people; corporate rule; moderate law; TL 11. Trade: Ni, Po.
WalstonC544338-8Routine port; small low-G world; thin tainted air (filter); 40% water; ~3,000 people; oligarchy; high law (Law 8 — blades & stunners banned); TL 8. Trade: Lo.
567-908E532000-0Frontier pad only; small low-G world; very thin air (respirator); 20% water; uninhabited; no government; no law; TL 0. Trade: Ba, Po.

Notes

  • This sheet is player-facing — keep spoilers and GM-only world detail in GM Notes/.
  • Values follow the 2022 Update Core Rulebook. Size-based gravity here uses the rulebook’s Size table; a couple of system rundowns quote slightly rounded figures (e.g. “~0.6 G” for Size 6) — trust the table for the canonical number.
  • The trade-code list above is the Core Rulebook set. Extended/Travellers’ codes (capital-world Cp/Cx, the Importance Ix / Economic Ex / Cultural Cx extensions) come from sector sourcebooks and are not part of the Core UWP.