Yes, all decimals are rational numbers. A rational number is any number that can be expressed as the quotient or fraction p/q of two integers, where p is the numerator and q is the non-zero denominator. Decimals, whether terminating or repeating, can always be expressed as fractions.
For example, the decimal 0.5 can be written as 1/2, and the repeating decimal 0.333... can be written as 1/3. Even non-repeating, non-terminating decimals like 0.1010010001... can be expressed as fractions, although the fractions may be more complex.
Therefore, all decimals, regardless of their form, are rational numbers because they can be represented as fractions of integers.