There is no single general legal definition of Youth or Young people in the Czech Republic. The legal system defines 'Youth' in both Civil and Criminal codes differently and the same is true for other sectoral policies, such as social, employment or health policy. The general perception of Youth is also differing.

The political definition of Youth was embodied in the last available National Youth Strategy and included young people between 13-30 years of age. The overall State Strategy focused on the age group 0 - 30 years of age and thus encompasses children as well. 

Youth Policy Strategy was agreed by the Government with the Strategy supporting Youth for years 2014-2020 (Koncepce podpory mládeže na období 2014-2020, Governmental Decree no. 342 of 12 May 2014).

The previous governmental Youth Strategy 2007-2013 (Koncepce státní politiky pro oblast dětí a mládeže na období 2007-2013) considered Youth to be up to 26 years of age. No lower limit was set, as the Strategy focused on children as well. However, a category of 'social youth' aged up to 30 was also recognised, but not in the political sense. 

In general, we can divide the age groups according to the following terminology

Children (děti) 0 - 13/15/18 years of age. The upper limit differs according to the context. Legally 18 years of age is the end of 'being a child'.

Youth (mládež) 13/15 - 18/24/26/30 years of age. The lower limit is a sociological and political definition. By 15 years of age young people gain citizen duties. The upper limit is different in a spoken context. General public usually considers Youth up to 18 years of age or up to 26 years.

Juvenile (mladiství, dorost) 15-18 years of age.

In a sporting environment various other differentiations can be used, of younger youth (mladší dorost, 13-14 years), middle youth (střední dorost, 15-16 years) and older youth (starší dorost, 17-18 years). In some sports 'dorost' could be meant up to 15 years, in some up to 18 years, in some other up to 23 years of age. Often the term 'junioři' (juniors) is also used, where the upper limit is also different in various contexts.

In the health environment, 'dorost' is usually used up to 18 years of age, but experts also use it for those 19 years of age (up to 20 years of age). 

Age limits linked to rights and obligations are split in several law acts

Civil Code (Act No. 9/2012 Sb.)

• Full legal competence is achieved at the age of 18 years, 16 years in special cases (please see section 1.2 National Youth Law)
• Distinguishes only minors with limited legal competence and majors with full legal competence

Criminal Code (Act No. 40/2009 Sb.)

• Defines the Child as a person up to 18 years of age
• Uses the term “age close to the juvenile age” which is not defined by the law but is left to the court’s discretion (ca. up to 20 years depending on mental and social maturity of the person)

Labour Code (Act. No. 262/2006 Sb.)

• Defines "juvenile worker" as up to 18 years of age

Other responsibilities connected with the age of 26 years

• Health insurance is no longer provided by the state even if the person is still a university student (No. 48/1997 Sb.; No. 592/1992 Sb.)
• Certain tax relief is no longer applicable (another threshold is set for 28 years in case you are engaged in a Ph.D. programme)