Dech

deCH is a shorthand widely used in linguistics and localization to refer to the German language as it is used in Switzerland. In formal tagging systems, the locale code for German in Switzerland is de-CH, where CH stands for Confoederatio Helvetica, the Latin name of the Swiss Confederation. The term deCH thus encompasses two closely related but distinct linguistic strata: Swiss German dialects and Swiss Standard German.

Swiss German dialects (Schweizerdeutsch) belong to the Alemannic group and are the forms most commonly spoken in everyday conversation across Switzerland. They vary by region and are typically not used in formal writing; they coexist with Swiss Standard German in education and official media. Swiss Standard German (Schweizer Hochdeutsch) is used in formal communication, education, literature, and most national media, and it incorporates Swiss vocabulary and some regional spellings.

In multilingual Switzerland, deCH can also function as a locale tag in software, websites, and documentation to tailor language, spelling, and date formats to Swiss German norms, such as the use of certain regional terms and formatting conventions.

Notes: Although de-CH is the official code, the linguistic reality includes a spectrum from local dialects to standardized German as written for Swiss contexts.

See also: German language in Switzerland; Swiss German; Swiss Standard German; language tagging.