Roman currency was based on a silver denarius, struck at 84 to the Roman pound (322.5 grs.), that was exchanged against gold coins or base metal fractional denominations collectively called aes (a term that refers to copper and any of its alloys). The gold aureus, struck at 40 to the Roman pound, and the denarius were minted from virtually pure metal (99-99.5% fine). In 23 B.C. Augustus reformed theaes so that fractional denominations were struck in two metals orichalcum or brass (75% copper; 20% zinc; 5% tin) and pure copper. The rate of exchange was 1 aureus = 25 denarii = 100 brass sestertii = 400 copper asses. Romans reckoned large sums in the sestertii (abbreviated HS), although they paid in aurei or denarii.










Equivalent Value








In Denarii


In Asses






7.90 grs.










3.80 grs.










3.80 grs.










1.90 grs.










25.00 grs.










12.50 grs.










11.00 grs.










3.25 grs.










3.00 grs.





*Denomination introduced by Nero, 64-68 A.D.


In 64, Nero reduced the standard of the aureus to 45 to the Roman pound (7.20 grs.) and of the denarius to 96 to the Roman pound (3.30 grs.). He also lowered the denarius to 94.5% fine. Successive emperors lowered the fineness of the denarius; in 180 Commodus reduced its weight by one-eighth or 108 to the pound.




Date Weight Purity Weight


64-68 3.18 grs.   93.5% 2.97 grs.

70-81 3.22 grs.   90.0% 2.87 grs.

82-85 3.33 grs.   98.0% 3.26 grs.

85-107 3.27 grs.   93.5% 3.04 grs.

107-148 3.21 grs.   89.0% 2.88 grs.

148-161 3.23 grs.   83.5% 2.68 grs.

161-168 3.23 grs.   79.0% 2.57 grs.

168-170 3.24 grs.   82.0% 2.67 grs.

170-180 3.26 grs.   79.0% 2.57 grs.

180-185 3.07 grs.   76.0% 2.34 grs.

186-192 2.98 grs.   74.0% 2.22 grs.



Severan emperors (193-235) steadily debased the denarius from a standard of 78.5% to 50% fine; in 212 Caracalla reduced the weight of the aureus from 45 to 50 to the Roman pound. They also coined aes from a bronze alloy with a heavy lead admixture and discontinued fractional denominations below the as.




Date Weight Purity Silver Weight


Pertinax 193 3.16 grs. 87.0% 2.75 grs.

Didius Julianus, 193 2.95 grs. 81.5% 2.40 grs.

Septimius Severus, 193-194 3.14 grs. 78.5% 2.46 grs.

Septimius Severus, 194-196 3.07 grs. 64.5% 1.98 grs.

Septimius Severus, 196-211 3.22 grs. 56.5% 1.81 grs.

Caracalla, 212-217 3.23 grs. 51.5% 1.66 grs.

Macrinus, 217-218 3.15 grs. 58.0% 1.82 grs.

Elagabalus, 219-222 3.05 grs. 46.5% 1.41 grs.

Severus Alexander, 222-228 3.00 grs. 43.0% 1.30 grs.

Severus Alexander, 229-230 3.24 grs. 45.0% 1.46 grs.

Severus Alexander, 230-235 2.94 grs. 50.5% 1.50 grs.

Maximinus, 235-238 3.07 grs. 46.0% 1.43 grs.

Gordian I & II, 238 2.77 grs. 63.0% 1.71 grs.

Pupienus & Balbinus, 238 2.80 grs. 55.0% 1.55 grs.

Gordian III, 241 3.03 grs. 48.0% 1.46 grs.


In 215 Caracalla introduced the antoninianus (5.1 grs.; 52% fine) a double denarius, containing 80% of the silver of two denarii. The coin invariably carried the radiate imperial portrait. Elagabalus demonetized the coin in 219, but the senatorial emperors Pupienus and Balbinus in 238 revived the antoninianus as the principal silver denomination which successive emperors reduced to a miserable billon coin (2.60 grs.; 2% fine).




Date Weight Purity Silver Weight


Pupienus & Balbinus, 238 4.79 grs. 49.5% 2.38 grs.

Gordian III, 238 4.50 grs. 48.5% 2.20 grs.

Gordian III, 241 4.43 grs. 44.5% 1.98 grs.

Gordian III, 243 4.16 grs. 41.5% 1.62 grs.

Philip, 244 4.12 grs. 43.0% 1.74 grs.

Philip, 248 4.12 grs. 47.0% 1.94 grs.

Trajan Decius, 250 3.97 grs. 41.0% 1.64 grs.

Trebonianus Gallus, 251 3.46 grs. 36.0% 1.26 grs.

Aemilian, 253 3.53 grs. 35.5% 1.26 grs.

Valerian, 253 3.10 grs. 22.0% 0.68 grs.

Valerian, 255-60 3.07 grs. 19.0% 0.58 grs.

Gallienus, 260 3.03 grs. 18.0% 0.54 grs.

Gallienus, 261-63 2.97 grs. 15.5% 0.46 grs.

Gallienus, 263-65 2.75 grs. 13.0% 0.38 grs.

Date Weight Purity Silver Weight


Gallienus, 265-66 2.81 grs.  9.0% 0.31 grs.

Gallienus, 267-68 2.69 grs.  6.0% 0.16 grs.

Claudius II, 268 2.95 grs.  3.0% 0.09 grs.

Claudius II, 269 2.60 grs.  2.0% 0.05 grs.

Claudius II, 270 3.39 grs.  3.0% 0.10 grs.

Aurelian, 270 3.15 grs.  2.5% 0.08 grs.

Aurelian, 274 3.88 grs.  5.0% 0.20 grs.


In 274, the emperor Aurelian reformed the currency and his denominations remained in use until the great recoinage of Diocletian in 293. Aurelian struck a radiate aurelianianus of improved weight (84 to the Roman pound) and fineness (5% fine) that was tariffed at five notational denarii communes ("common denarii" or d.c.). The denomination carried on the reverse the numerals XXI (or in Greek KA) to denote the coin as equal to 20 sestertii (or 5 d.c.). The aureus (minted at 50 or 60 the Roman pound) was exhanged at rates of 600 to 1,000 d.c., equivalent to 120 to 200 aurelianiani. Rare fractions of billion denarii, and of bronze sestertii and asses were also coined. Simultaneously, Aurelian reorganized the provincial mint at Alexandria, and he minted an improved Alexandrine tetradrachma that might have been tariffed at par with the aurelianianus.


The emperor Tacitus in 276 briefly doubled the silver content of the aurelianianus and halved its tariffing to 2.5 d.c. (hence coins of Antioch and Tripolis (in Phoenicia) carry the value marks X.I), but Probus (276-282) immediately returned the aurelianianus to the standard and tariffing of Aurelian, and was the offical tariffing down to the reform of Diocletian in 293.






Romans measured dry capacity (grain) by the MODIUS (8.75 liters or 1.1 peck; by weight just over 6-2/3 kilogrs. or 14-2/3 lbs.) and wet capacity (oil and wine) by the AMPHORA (26 liters or nearly 7 gallons). The amphora was three times the volume of the modius. In markets, oil and wine were usually cited by the sextarius (0.539 liters or just under 1 pint).




1 modius = 16 sextarii 1 culleus = 20 amphorae

1 sextarius = 16 cyathi 1 amphora = 48 sextarii

1 sextarius = 16 cyathi


In the Price Edict (301), Diocletian priced many items by the MODIUS CASTRENSIS ("camp modius"), equivalent to 1.5 modii.


Greeks measured grain by the MEDIMNOS (25 kilgrs. or 55 lbs.), equal to 6 Roman modii. In Egypt grain was measured by the ARTABA (18.75 kilgrs. or 41.3 lbs.), equal to 4.5 modii. Greeks measured wet capacity by the METRETES, divided into 12 choes = 144 kotylai = 864 kyathoi. The KOTYLE was half of the Roman SEXTARIUS.


In the Principate, an adult male required 4 modii as his monthly ration of wheat, which probably represented two-thirds of his caloric intake (with oil, vegetables, and protein making up the other third). The Roman soldier was allotted 1 cyathus (1/16 sextarius) of olive oil and 1 to 2 sextarii of wine per day. A peasant family of four consumed an annual minimum of 120 modii of wheat, 120 sextarii of olive oil, and possibly 720 sextarii of wine (often mixed with vinegar as posca).




Romans measured area by the amount ploughed in a day by a yoke of oxen. Land was reckoned by the IUGERUM (28,000 square Roman feet or 5/8 of an acre). A farm of 10 iugera (5-6 acres or 2.5 hectares) could provide a plebian family of most of its annual subsistence needs. In Egypt, land was measured by the AROURA (equal to 1.1 iugera).




Romans measured distance by the mile, mille passuum ("one thousand of paces"), equivalent to 1,620 English yards or 92% of the English mile. 1 Roman mile = 1,000 paces (passus) = 5,000 feet (pedes). An average day's march for a Roman army was 15 to 17 miles; a forced march (magnum iter) was 20 to 25 miles.




In the Greek-speaking East, provincial and city mints struck traditional currency based on a silver drachma. Each drachma was divided into six obols; each obol was in turn divided into 8 chalci. The exchange was 1 drachma = 6 obols = 48 chalci. In the Classical age, the Greeks minted silver drachmae and obols, along with their multiples and fractions of the drachma or obol. Since weight standards varied throughout the Greek world, the weight of the drachma varied from city to city. In the second century B.C., the Greeks cities also created a base metal fractional currency premised on either a bronze obol or, in Egypt, a bronze drachma. The result was a bewildering array of local silver and bronze coins in the Roman East. The major currency systems were as follows:


1. ATTIC STANDARD, the international standard of the Greek world, based on a silver drachma of Athens that was equal to the Roman denarius. Greek authors cite large sums of money in Attic drachmae rather than Roman denarii or sestertii. The following silver denominations were minted in the Roman age:


Tetradrachma = 4 drachmae

Tridrachma = 3 drachmae

Didrachma = 2 drachmae

Drachma = 1 drachma

Hemidrachma = 1/2 drachma


The Attic standard was used in Greece, Macedon, eastern and southern Asia Minor (Lycia, Cilicia, and Cappadocia), and the southern Levant (Phoenicia, Judaea, Arabia). In the Near East silver coins of Attic weight were called "silver of the standard of Tyre," the Phoenician port famed for her trade coins, the silver tetradrachmae with the striding eagle. Judas received Tyrian tetradrachmae as his thirty pieces of silver. Most cities minted bronze fractions based on an obol (1/6 of a denarius) that stood in no convenient relationship to Roman base metal coins. Large bronze didrachmae and drachmae were struck as proxies for silver coins, but cities usually minted a wide array multiples and fractions of the obol and chalcus.


2. CISTOPHORIC STANDARD. This was based on a silver drachma that was only 75% the weight of the denarius; the standard was used in Crete, Rhodes, western Asia Minor (Asia, Bithynia, and Pamphylia), and in northern Syria (where it was called the Antiochene standard). The most famed silver coins of this standard were silver cistophori (= 3 denarii) struck by the Asian cities of Pergamum and Ephesus, and tetradrachmae (= 3 denarii) of Antioch in Syria. Fractional bronze coins were based on a bronze obol that was exchanged against 2 Roman asses (or assaria in Greek) so that bronze coins in this system were easily equated to Roman aes.


3. ALEXANDRINE STANDARD. This was the standard of Alexandria, capital of Egypt. Initially, the Romans employed Ptolemaic regal coins: the bronze obol and drachma, and low grade silver tetradrachma tariffed at 1.5 denarii. In 41/2 A.D. Claudius introduced tetradrachmae (four drachmae pieces) minted from billon, an alloy less than 25% silver, and equal to 1 silver denarius. Bronze fractions were based on the drachma and obol. Egyptian provincial coins were thus FIDUCIARY so that Roman authorities enforced them as the sole legal tender and excluded all other coins, especially gold and silver coins. The exchange was 1 billon tetradrachma = 4 bronze drachmae = 24 bronze obols. In Roman tax collection, premiums were charged on payments in bronze so that the tetradrachma was often exchanged at rates of 25 to 29 obols.






(c. 50 B.C.-235 A.D.)



WAGES. Roman soldiers received top pay for coveted full time employment. The legionary from 46 B.C. to 84 A.D. received a daily wage of 10 asses or 225 denarii per year; Praetorian guardsmen received 2 denarii per day or 720 denarii per year. Domitian raised legionary annual pay by one-third to 300 denarii. Septimius Severus in 195 and Caracalla in 215 raised the annual pay to 400 and 600 denarii respectively.


Pompeian laborers in 50 B.C.-79 A.D. earned daily wages of 5 to 16 asses, but employment was seasonal. In the second century A.D. skilled miners in Dacia earned 6 to 10 asses per day plus room and board when hired on 6 or 8 month contracts.


PRICES. The best index of the purchasing power of salaries comes from the price of grain, which represented two-thirds to three-quarters of the caloric intake of an adult male. Prices suffered regional and seasonal fluctuations, but averages were as follows:


Rome 1 modius 1 to 1.5 denarii

Italy 1 modius 1 denarius

Asia Minor 1 modius to 1 denarius

Africa 1 modius 6 asses to 1 denarius

Egypt[1] 1 modius denarius


The market price of an adult male's annual need of grain, 60 modii, was 60 denarii in Italy or 26.7% of the annual salary of a legionary. A peasant family of four required annually 150 modii of grain priced in the market at two-thirds of the annual salary of a legionary. Aristocratic patrons during festivals in Italian and African towns handed out sportula to poorer citizens at the rate of 1/2 or 1 denarius per man. Each citizen could thus buy 20-25% of his monthly needs for grain.


In Italy, 2 copper asses (1/8 denarius) bought the minimum daily dietary needs so that 45 to 50 denarii per year was the subsistence wage. In Asia Minor and Syria, the equivalent price for daily need was one 1 bronze obol (= 2 assaria). Market wardens (agoranomoi) of Ephesus in 150-200 A.D. fixed prices for 1 pound of wheat bread (capable of feeding an adult male) at 2 to 4 bronze obols (= 1/4 to 1/2 denarius).

[1]Price expressed as 1 artaba of wheat at 2 tetradrachmae.