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Roman Numerals Converter

Convert numbers to Roman numerals and back, instantly. Bidirectional, with a place-value breakdown, a date-to-Roman tattoo mode, and support up to 3,999,999.

Type in either box — the other updates instantly.

Lowercase, IIII, and _V (×1000) all work.

In Roman numerals

MCMXCIV

How it breaks down

Each place value of 1,994, largest first.

M

1,000

adds 1,000
+
CM

900

⁨C⁩ before ⁨M⁩ → ⁨M⁩ − ⁨C⁩ = 900
+
XC

90

⁨X⁩ before ⁨C⁩ → ⁨C⁩ − ⁨X⁩ = 90
+
IV

4

⁨I⁩ before ⁨V⁩ → ⁨V⁩ − ⁨I⁩ = 4
=

1,994

Try one

50L
100C
500D
1,000M
2,000MM
1,994MCMXCIV
1,984MCMLXXXIV
1,993MCMXCIII
1,995MCMXCV
2,004MMIV

Roman numerals converter. Turn any number or date into Roman numerals and read them back.

A Roman numerals converter turns a number into Roman numerals (like 1994 into MCMXCIV) and reads any Roman numeral back into a number. It also formats dates for tattoos and engravings, breaks every result into its place values, and handles numbers past 3,999 using the overline (vinculum) that multiplies a symbol by 1,000.

What Are Roman Numerals?

Roman numerals are the number system of ancient Rome, written with seven letters of the Latin alphabet — I, V, X, L, C, D, and M — instead of the ten digits 0-9 in everyday use today. Each letter has a fixed value (I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1,000), and you build a number by placing those letters in order from largest to smallest and adding them up, with six special "subtractive" pairs (IV, IX, XL, XC, CD, CM) that let you write 4, 9, 40, 90, 400, and 900 without repeating a symbol four times.
Unlike the Hindu-Arabic system we normally write in, Roman numerals have no place value and no symbol for zero — the Romans counted from one and never needed a zero in a system built for tallying and pricing goods. That is also why they top out early: the largest number you can write with plain letters is 3,999 (MMMCMXCIX). To go higher, a bar called a vinculum is drawn over a numeral to multiply it by 1,000, which stretches the range to 3,999,999.
Roman numerals disappeared from arithmetic centuries ago but survive everywhere you look for a touch of tradition: clock and watch faces, book chapters and outline headings, monarch and pope names (Louis XIV, Charles III), Super Bowl and Olympic numbering, and the copyright year in film and TV credits. They are also one of the most popular number systems for tattoos, because a birthday or anniversary written as XV • VI • MCMLXXXV reads as timeless rather than dated. This converter handles all of those needs in one place: type a number to get its Roman form, paste a Roman string to decode it, or switch to the date tab to format a full date — with a plain-language breakdown of every answer so you can see exactly how it was built.

How to Read and Write Roman Numerals

Every Roman numeral is built from the same seven symbols. Learn these and the rest is just ordering and adding.
SymbolValueMemory hook
I1a single tally mark
V5one hand, five fingers
X10two hands crossed
L50half of a hundred
C100C for *centum* (Latin for 100)
D500half of a thousand
M1,000M for *mille* (Latin for 1,000)
There are four rules that decide how the letters combine:
1. Add when values go large to small. A bigger or equal symbol followed by a smaller one is added: VI = 5 + 1 = 6, LXXVII = 50 + 10 + 10 + 5 + 1 + 1 = 77.
2. Subtract with one of six pairs only. When a smaller symbol sits directly before a larger one, subtract it — but only in these six combinations: IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900). The rule underneath is simple: I is placed only before V or X, X only before L or C, and C only before D or M.
3. Repeat a symbol at most three times. You can write III (3) or XXX (30), but not IIII or XXXX in standard form — that is why 4 is IV, not IIII. Only I, X, C, and M can repeat at all.
4. Never repeat or subtract V, L, or D. These five-based symbols appear at most once and are never used to subtract, so forms like VV, LL, or IL are invalid.
To write a number by hand, split it into place values and convert each part separately. Take 1994:
1. Thousands: 1,000 = M.
2. Hundreds: 900 = CM.
3. Tens: 90 = XC.
4. Units: 4 = IV.
Join them left to right and you get M + CM + XC + IV = MCMXCIV.
To read a numeral back, scan left to right and add each symbol, subtracting whenever a smaller symbol comes before a larger one. MCMXCIV reads as M (1,000), then CM (900), then XC (90), then IV (4), which sums to 1,994.
To use this converter, type a number in the number box to see its Roman form, or type a Roman numeral in the other box to decode it — both boxes stay linked and update as you type, so there is no button to press. Every result shows a place-value breakdown underneath, and you can click the result to copy it. For a full date, switch to the Date tab, enter the day, month, and year, and pick the order and separator you want. The tool accepts lowercase (mcmxciv), the clock-face form IIII, and an underscore for the overline (type _V for 5,000), and it flags genuinely invalid input such as IC with a "did you mean XCIX?" suggestion instead of silently returning a wrong answer.

Roman Numerals Chart: Common Numbers and Recent Years

NumberRoman numeralBuilt from
1I
2III + I
3IIII + I + I
4IVV − I
5V
6VIV + I
7VIIV + I + I
8VIIIV + I + I + I
9IXX − I
10X
20XXX + X
30XXXX + X + X
40XLL − X
50L
60LXL + X
70LXXL + X + X
80LXXXL + X + X + X
90XCC − X
100C
400CDD − C
500D
900CMM − C
1,000M
2,000MMM + M
3,000MMMM + M + M
2,024MMXXIVMM + XX + IV
2,025MMXXVMM + XX + V
2,026MMXXVIMM + XX + VI
2,027MMXXVIIMM + XX + VII
2,030MMXXXMM + XXX
2,040MMXLMM + XL
2,050MMLMM + L

Worked Roman Numeral Examples

2026 in Roman numerals is MMXXVI

Type 2026 into the number box and the converter returns MMXXVI. The breakdown shows how it is built: MM = 2,000 (two thousands), XX = 20 (two tens), and VI = 6 (five plus one). There is no subtractive pair here because none of 2,000, 20, or 6 lands on a 4 or 9, so the whole numeral is purely additive: MM + XX + V + I = 2,026. Neighboring years follow the same pattern — 2024 = MMXXIV (the IV is the only subtractive part), 2025 = MMXXV, and 2027 = MMXXVII.

Writing a birthday as a Roman-numeral date

Switch to the Date tab to format a full date for a tattoo, ring, or engraving. Enter 15 June 1985 with the order set to Day-Month-Year and the dot separator, and the converter produces XV • VI • MCMLXXXV — that is 15 (XV), 6 (VI), and 1985 (MCMLXXXV). Change the order to Month-Day-Year and the same date becomes VI • XV • MCMLXXXV, which is why the order you choose matters enormously on something permanent: XII • XI and XI • XII are two different dates. The tool decodes MCMLXXXV as M (1,000) + CM (900) + LXXX (80) + V (5) = 1,985, so you can verify every part before it goes on skin or metal.

Decoding a Super Bowl or a copyright year

Roman numerals are easiest to trust when you can watch them add up. Paste LVIII and the converter reads it left to right as L (50) + V (5) + III (3) = 58 — Super Bowl LVIII was the 58th game. The NFL numbers every Super Bowl this way, with one exception: the 50th game was branded "Super Bowl 50" rather than "Super Bowl L", then numbering resumed with LI. The same skill decodes the copyright year in film and TV credits: MCMLXXVII is M (1,000) + CM (900) + L (50) + X (10) + X (10) + V (5) + II (2) = 1977, the year the first Star Wars was released. Studios use Roman numerals partly for prestige and partly because a year in letters is harder to read at a glance.

Why clock faces show IIII instead of IV

Most Roman-numeral clocks and watches print 4 o'clock as IIII, not the standard IV — while still using IX for 9. The tradition goes back to very early clocks such as the Wells Cathedral clock of the late 14th century, and no single reason is proven. The most cited explanation is visual balance: the heavy four-character IIII sits opposite the equally heavy VIII at 8 o'clock, giving the dial symmetry that a light IV would break. Other theories point to a king (Charles V of France) who disliked IV, or simply to older additive habits from before subtractive notation became standard. This converter treats IIII as a correct 4 and adds a short note that IV is the modern written standard — so it teaches the exception instead of marking you wrong.

Numbers past 3,999: the vinculum (overline)

Standard Roman numerals stop at 3,999 (MMMCMXCIX) because no symbol may repeat more than three times. To go higher, a bar called a vinculum is drawn over a symbol to multiply it by 1,000. That is why 4,000 is written I̅V̅ (an overlined IV) rather than the illegal MMMM. This converter supports the vinculum all the way to 3,999,999:
NumberRoman numeralHow the overline works
4,000I̅V̅IV (4) with an overline, 4 × 1,000
5,000V (5) overlined, 5 × 1,000
10,000X (10) overlined
50,000L (50) overlined
100,000C (100) overlined
1,000,000M (1,000) overlined = one million
3,999,999M̅M̅M̅C̅M̅X̅C̅I̅X̅CMXCIXthe largest value the tool supports
The overline is a display trick, so when you copy a large numeral the tool preserves the bar as a self-contained character and also offers an underscore version (_IV for 4,000) for apps that strip the line — the one place most converters silently lose the ×1,000 meaning.

Why IC is not 99 (and what the tool suggests)

A classic error is writing 99 as IC — "one less than a hundred." It looks logical, but it breaks the subtractive rule: I may only be placed before V or X, never before C. Paste IC and this converter does not silently return 99; it flags the input as invalid and suggests the correct form, XCIX, which is XC (90) + IX (9) = 99. The same guardrail catches IL (should be XLIX for 49), IM (should be CMXCIX for 999), and VV (V is never repeated — you meant X). Teaching the fix rather than accepting a bad guess is the whole point of a converter you can trust for permanent uses like tattoos and inscriptions.

Common Roman Numeral Mistakes to Avoid

  • Writing IIII for 4 in ordinary text. IIII is accepted on clock dials by tradition, but in documents, tattoos, and formal writing the standard form is IV. This converter reads IIII as 4 and reminds you that IV is the modern spelling.
  • Inventing subtractive pairs like IC, IL, or IM. Only six pairs exist (IV, IX, XL, XC, CD, CM). IC is not 99 — the correct form is XCIX; IL is not 49 — it is XLIX; IM is not 999 — it is CMXCIX.
  • Repeating V, L, or D. These symbols appear at most once, so VV, LL, and DD are always invalid. Ten is X (not VV), 100 is C (not LL), and 1,000 is M (not DD).
  • Using a symbol more than three times in a row. IIII, XXXX, and CCCC are not standard; use the subtractive forms IV, XL, and CD instead. Only I, X, C, and M repeat at all, and never past three.
  • Getting the date order wrong on something permanent. XI • XII and XII • XI are different dates. Decide on Day-Month-Year or Month-Day-Year before you engrave or tattoo, and verify each part with the breakdown.
  • Trusting a plain copy of an overlined numeral. If you copy a large numeral and the bar vanishes, V̅ (5,000) turns into V (5) — a silent 1,000-fold error. Use this tool's overline-safe copy or its underscore form (_V) for apps that drop the line.

Tips for Getting Roman Numerals Right

  • Break big numbers into place values first. Convert the thousands, hundreds, tens, and units separately, then join them — 1994 becomes M + CM + XC + IV = MCMXCIV. The converter shows this split for every result so you can double-check the logic, not just the answer.
  • For a tattoo or engraving, verify with two sources and screenshot the result. A Roman numeral is permanent, so decode it back to the number to confirm, and save an image rather than copying the text — an overline or a font substitution can change on the way to a designer.
  • Read an unfamiliar numeral left to right and add as you go, subtracting only at a small-before-large step. LVIII is 50 + 5 + 1 + 1 + 1 = 58; XCIX is (100 − 10) + (10 − 1) = 99. Watching the running total is the fastest way to check a copyright year or Super Bowl number.
  • Pick IIII or IV on purpose for clock and watch projects. IIII is the traditional dial form and balances VIII across the face; IV is the textbook standard. Neither is wrong — just be consistent with the look you want.
  • Remember there is no zero and no fraction. If your value is 0, negative, or has a decimal, Roman numerals cannot express it — the Romans wrote the word nulla for none. Round to a whole number, or use ordinary digits for anything below one.
  • Choose a separator that reads clearly at small sizes. For dates, a dot or bullet (XV • VI • MCMLXXXV) stays legible on jewelry, while slashes and dashes can blur; the Date tab lets you preview each option before you commit.

Key Roman Numeral Terms

Roman numeral

A number written with the seven Latin letters I, V, X, L, C, D, and M, using addition and a few subtractive pairs rather than the place-value digits of the Hindu-Arabic system.

Additive notation

The default rule: symbols placed from largest to smallest are added together. LXVI is 50 + 10 + 5 + 1 = 66. Most of a numeral is additive.

Subtractive notation

A shorthand where a smaller symbol before a larger one is subtracted, used in exactly six pairs — IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900).

Subtractive pair

One of the six allowed two-letter combinations that subtract. The underlying rule is that I precedes only V or X, X only L or C, and C only D or M.

Vinculum

A horizontal bar (overline) drawn above a numeral to multiply its value by 1,000. V with a vinculum is 5,000; it extends the range of Roman numerals from 3,999 up to 3,999,999.

Nulla

The Latin word for "none," used in the Middle Ages to stand in for zero, which Roman numerals have no symbol for. Around 725, Bede also used the letter N for the same purpose.

Apostrophus

An older, pre-vinculum way of writing large numbers (500 as I followed by a reversed C, 1,000 as CIↃ). It is historical only — modern converters and this tool use the vinculum instead.

Standard form

A Roman numeral that follows all modern rules — correct subtractive pairs, no symbol repeated more than three times, and V, L, or D never repeated or subtracted. MMMCMXCIX (3,999) is the largest standard form without a vinculum.


Roman Numerals Converter — Frequently Asked Questions

What is 2026 in Roman numerals?

2026 in Roman numerals is MMXXVI. It breaks down as MM (2,000) + XX (20) + VI (6). Nearby years are 2024 = MMXXIV, 2025 = MMXXV, and 2027 = MMXXVII.

How do I write a date or birthday in Roman numerals?

Convert the day, month, and year separately, then join them with a separator. For 15 June 1985 in Day-Month-Year order with dots, you get XV • VI • MCMLXXXV. Use this converter's Date tab to set the order (Day-Month-Year or Month-Day-Year) and separator, and always decode the result back to numbers before you engrave or tattoo it, since a permanent date has no undo.

Why is 4 written as IV and not IIII?

Because a symbol cannot repeat more than three times in standard form, so IIII is not allowed. Instead, 4 uses the subtractive pair IV — one (I) before five (V), meaning "one less than five."

Why do clocks use IIII instead of IV?

Many clocks and watches show IIII at 4 o'clock by tradition, going back to early clocks like the late-14th-century Wells Cathedral clock. No single reason is proven, but the most common explanation is visual balance — the four-stroke IIII mirrors the heavy VIII across the dial. Some accounts credit a king who disliked IV, and others point to older additive habits. This converter accepts IIII as a valid 4 and notes that IV is the modern written standard.

What is the largest Roman numeral?

In standard notation the largest is 3,999, written MMMCMXCIX, because no symbol may repeat more than three times. Using the vinculum — a bar over a symbol that multiplies it by 1,000 — this converter reaches 3,999,999, written with overlines as M̅M̅M̅C̅M̅X̅C̅I̅X̅CMXCIX.

Is there a Roman numeral for zero?

No. Roman numerals have no symbol for zero and start counting at one. When medieval scholars needed a zero, they wrote the Latin word nulla ("none"); around 725, Bede used the letter N for the same idea.

How are numbers over 3,999 written in Roman numerals?

With a vinculum — a horizontal bar drawn over a numeral that multiplies its value by 1,000. So 4,000 is I̅V̅ (an overlined IV), 5,000 is V̅, and 1,000,000 is M̅. This avoids illegal forms like MMMM and lets the system reach 3,999,999. When copying a barred numeral, keep the overline or use this tool's underscore form (_V) so it does not collapse back to the small value.

Can I write IIII for 4, or is that wrong?

It depends on the context. IIII is fully accepted on clock and watch faces and appears on many historical inscriptions, so it is not "wrong" there. For documents, tattoos, and formal writing, IV is the modern standard. This converter reads IIII as 4 and adds a note pointing you to IV, rather than rejecting it.

What does LVIII mean, like in Super Bowl LVIII?

LVIII is 58, read as L (50) + V (5) + III (3). The NFL numbers each Super Bowl in Roman numerals, so Super Bowl LVIII was the 58th game. The one exception was Super Bowl 50, which was branded with the digit 50 rather than the letter L before numbering resumed at LI.

What is the difference between Roman and Arabic numerals?

Arabic numerals are the ten digits 0-9 with place value, so position determines a digit's worth (the 2 in 205 means 200). Roman numerals use seven letters with no place value and no zero, building numbers by adding symbols and subtracting in six special pairs. Arabic numerals handle arithmetic and large numbers far more easily, which is why Roman numerals survive mainly for dates, names, and decoration.

How accurate is this Roman numerals converter, and can I trust it for a tattoo?

The conversion is exact in both directions across the full 1 to 3,999,999 range — every number has one canonical Roman form, and the tool shows the place-value breakdown so you can verify it yourself. It also validates input, flagging invalid strings like IC and suggesting the correct XCIX instead of guessing. For a permanent tattoo or engraving, still confirm the date order and decode the result back to numbers before committing, because the ink cannot be edited later.

Is this Roman numerals converter free?

Yes. It runs entirely in your browser with no account and no sign-up, converting both directions, formatting full dates, showing a breakdown of every result, and supporting numbers up to 3,999,999 with the vinculum. You can bookmark or share a specific conversion using the link, so a decoded year or a tattoo date is easy to send to a friend or a designer.