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.
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.
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.
The new version is downward compatible, so you can still use old data.
Literally 'backward compatible'. Less common than 下位互換 but used in some technical contexts.
This printer is backward compatible.
Phrase meaning 'has backward compatibility'.
This system is backward compatible, so the migration is smooth.