Everyday Converters

Standard Roman numerals from 1 to 3999, converted both ways, with validation of canonical forms like MMXXIV. Roman numerals in this range cover most historical dates, ancient texts, and modern use cases (like book chapters or movie sequels). The converter validates that Roman numerals follow canonical form rules — for example, always subtracting (IV for 4, not IIII) — ensuring the converted output is correctly formatted. You can convert decimal to Roman (2024 becomes MMXXIV) or Roman to decimal (MCMXC becomes 1990) instantly.

The data-size converter uses 1024-based steps between units, the convention common in computing for KB, MB, GB and TB. The computing convention (1 KB = 1024 bytes) differs from the decimal convention used in storage marketing (1 GB = 1000 MB), which is why your 1 TB drive shows as only ~931 GB in operating systems. This tool uses the technical computing standard, so 1 MB = 1024 KB = 1048576 bytes, matching what developers and system administrators expect. This convention also aligns with binary-based calculations like data transfer rates and memory allocation.

Yes — translate between MPG, litres per 100 km and km per litre to compare efficiency across regions. Different countries use different fuel efficiency metrics — the US uses MPG (miles per gallon), Europe uses L/100km (liters per 100 kilometers), and some regions use km/L (kilometers per liter). These metrics are not linear conversions, so direct comparison is impossible without calculation. The tool converts between all three formats instantly, allowing you to compare a US car's 30 MPG rating against a European car rated at 7.8 L/100km to determine which is more efficient.