How the conversion works
Before 15 February 1971 a pound was divided into 20 shillings, and each shilling into 12 pence, so there were 240 old pence in a pound. Decimalisation kept the pound but split it into 100 new pence. To convert, the converter turns your amount into old pence and then multiplies by 100/240.
That gives some tidy results and some untidy ones. A shilling is exactly 5p and sixpence is exactly 2½p, but a single old penny is 5/12 of a new penny: about 0.42p. The converter shows decimal pence first, with an approximation marker for recurring decimals, and a pound value rounded to the nearest new penny.
Quick reference
| Old money | In old pence | Decimal pence | Pounds, rounded to nearest penny |
|---|---|---|---|
| 1d | 1d | ≈ 0.4167p | £0.00 |
| 6d | 6d | 2.5p | £0.03 |
| 1s | 12d | 5p | £0.05 |
| 2s 6d (half a crown) | 30d | 12.5p | £0.13 |
| 10s | 120d | 50p | £0.50 |
| £1 1s (a guinea) | 252d | 105p | £1.05 |
| £3 6s 8d | 800d | ≈ 333.3333p | £3.33 |
| 19s 11d | 239d | ≈ 99.5833p | £1.00 |
≈ means approximately. A value rounded to £0.00 can still be worth a fraction of a new penny. Half-penny ties in the rounded pounds column are rounded upwards.
Reading amounts in old documents
You'll see old money written in several ways. £3 6s 8d is the formal style, while accounts often used dots or dashes: £3.6.8 or £3-6-8. Amounts under a pound were usually written with a slash, so 7/6 means seven shillings and sixpence and 12/- means twelve shillings exactly. The “d” comes from denarius, the Latin for penny, and “s” from solidus.
If a total in a ledger has more than 19 shillings or 11 pence (it happens in rough working), just type it in as written. The converter tidies it into the proper form.
Common questions
How much is a shilling in today's money?
A shilling has a decimal face value of exactly 5p, because there were 20 shillings in a pound and 100 ÷ 20 = 5. Its inflation-adjusted purchasing power depends on the year.
How much was an old penny worth in new pence?
One old penny is 5/12 of a new penny, about 0.42p. There were 240 old pence in a pound and 100 new pence.
What does 'd' mean in old money?
The d stands for denarius, a Roman silver coin. Pounds, shillings and pence were abbreviated £, s and d from the Latin librae, solidi and denarii.
Does this tell me what the money would buy today?
No: this converts the face value. To adjust for inflation, use the worth today calculator, which uses official price data back to 1800.
A ledger check: £3 6s 8d
A column entry of “3 · 6 · 8” under £, s and d headings is not £3.68. Multiply the pounds by 240 and the shillings by 12, then add the pence: (3 × 240) + (6 × 12) + 8 = 800 old pence. Divide by 240 to obtain £3⅓, or about £3.333333 in decimal pounds.
Enter 3 pounds, 6 shillings and 8 pence above. The result rounds to £3.33 when expressed to a whole new penny. If you have three such entries, add the old amounts before rounding: 3 × 800d = 2,400d = £10 exactly. Adding three rounded decimal amounts would give £9.99.
Choose the result that fits your question
- For checking an account, retain the original £sd amount or total farthings.
- For explaining the denomination to a modern reader, use decimal face value and state any rounding.
- For interpreting the cost of living, take the original amount and its year to the purchasing-power calculator.
A handwritten slash can look like a decimal point. Check neighbouring entries and the column headings before deciding what a mark means. The worked account guide shows how to preserve a transcription alongside your calculation.
Sources and calculation notes
Calculation notes updated . Report a correction.