Translation guide
Describes a newer version of something that can still work with older versions or data. In Japanese, this is usually expressed with the borrowed term 下位互換 (かいごかん) or the phrase 下位互換性がある.
Expressing that a newer system, software, or format can still use or work with older versions.
The standard technical term for 'downward compatible'. Often used in IT and engineering contexts.
このソフトウェアは下位互換があります。
This software is downward compatible.
A phrase meaning 'has downward compatibility'. More natural in full sentences than the noun alone.
新しいバージョンは下位互換性があるので、古いデータも使えます。
The new version is downward compatible, so you can still use old data.
Phrase meaning 'has backward compatibility'.
このシステムは後方互換性があるため、移行がスムーズです。
This system is backward compatible, so the migration is smooth.
Both terms are understood, but 下位互換 is more common in everyday tech contexts. 後方互換 is sometimes preferred in formal specifications. When in doubt, use 下位互換.
Literally 'backward compatible'. Less common than 下位互換 but used in some technical contexts.
このプリンターは後方互換があります。
This printer is backward compatible.