---
title: "343 in Roman numerals is CCCXLIII"
description: "343 in Roman numerals is CCCXLIII, written as 100 + 100 + 100 + 40 + 1 + 1 + 1. How it breaks down, how to write it, and the numbers either side."
url: https://atoneplace.net/roman-numerals/343/
site: "At One Place"
---

# 343 in Roman numerals

**343 in Roman numerals: CCCXLIII**

343 is written CCCXLIII in Roman numerals. That is 7 symbol groups added together, reading left to right from the largest value down.

## How it breaks down

*CCCXLIII = 100 + 100 + 100 + 40 + 1 + 1 + 1 = 343*

| Group | Value | Subtraction | Running total |
| --- | --- | --- | --- |
| C | 100 | — | 100 |
| C | 100 | — | 200 |
| C | 100 | — | 300 |
| XL | 40 | L − X | 340 |
| I | 1 | — | 341 |
| I | 1 | — | 342 |
| I | 1 | — | 343 |

## Why the smaller symbol comes first

CCCXLIII uses subtractive notation in one place: XL means L minus X, or 40. A smaller symbol placed before a larger one is subtracted from it rather than added, which is why IX is nine and not eleven.

Only six such pairs are valid — IV, IX, XL, XC, CD and CM. That restriction is what makes the notation unambiguous: IIII and IC both look like they should work, but neither is standard, and only one spelling of any number is correct.

## The symbols

| Symbol | Value | Used here |
| --- | --- | --- |
| I | 1 | yes — 3× |
| V | 5 | no |
| X | 10 | yes — 1× |
| L | 50 | yes — 1× |
| C | 100 | yes — 3× |
| D | 500 | no |
| M | 1,000 | no |

## The same number, other ways

- **In words:** Three hundred forty-three
- **Roman numeral:** CCCXLIII
- **Symbol count:** 8 characters
- **Binary:** 101010111
- **Hexadecimal:** 157

## The numbers either side

| Number | Roman numeral |
| --- | --- |
| 341 | CCCXLI |
| 342 | CCCXLII |
| 343 | CCCXLIII ← |
| 344 | CCCXLIV |
| 345 | CCCXLV |

## Common questions

### What is 343 in Roman numerals?

343 is CCCXLIII.

### What does CCCXLIII mean?

CCCXLIII is the Roman numeral for 343 — 100 + 100 + 100 + 40 + 1 + 1 + 1.

### How do you write 343 in Roman numerals?

Take the largest value that fits and repeat until nothing is left: C (100), then C (100), then C (100), then XL (40), then I (1), then I (1), then I (1). That gives CCCXLIII.

## Related pages

- [341 in Roman numerals](https://atoneplace.net/roman-numerals/341/)
- [342 in Roman numerals](https://atoneplace.net/roman-numerals/342/)
- [344 in Roman numerals](https://atoneplace.net/roman-numerals/344/)
- [345 in Roman numerals](https://atoneplace.net/roman-numerals/345/)
- [4 in Roman numerals](https://atoneplace.net/roman-numerals/4/)
- [9 in Roman numerals](https://atoneplace.net/roman-numerals/9/)
- [14 in Roman numerals](https://atoneplace.net/roman-numerals/14/)
- [19 in Roman numerals](https://atoneplace.net/roman-numerals/19/)
- [40 in Roman numerals](https://atoneplace.net/roman-numerals/40/)
- [42 in Roman numerals](https://atoneplace.net/roman-numerals/42/)
- [49 in Roman numerals](https://atoneplace.net/roman-numerals/49/)
- [50 in Roman numerals](https://atoneplace.net/roman-numerals/50/)

## Sources

- Calculated on this page — At One Place (/about/)