yConverter

Japanese rooms are measured in tatami mats (帖) — but not all tatami are the same size. yConverter converts between 9 regional standards with unrounded Shakkan-hō constants, so architects, real estate buyers, and Japan enthusiasts get exact results. Features: • Available in 5 languages — English, French, Japanese, Danish, Malay • 9 regional standards: – Kyo-ma (京間) – Chukyo-ma (中京間) – Edo-ma (江戸間) – Rokuichi-ma (六一間) – Ryūkyū-tatami (琉球畳, 3 variants) – Danchi-ma (団地間, 2 variants) • Mathematically exact conversions using unrounded Shakkan-hō constants • Formula input — type expressions like (1+2)/3 directly into any field • Bidirectional real-time conversion — update any field and all others recalculate instantly • Live formula preview while typing • Educational guide explaining the math behind each regional standard — selectable and copyable • Dark Mode support Localization is AI-assisted; we'd love your feedback to improve it.