> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/programming_tasks/n/numeric_separator_syntax.md).

# Numeric separator syntax

Sidef allows underscores as a separator character in numeric inputs.

```ruby
# Int
say 1_2_3;  # 123

# Binary Int
say 0b1_0_1_0_1; # 21

# Hexadecimal Int
say 0xa_bc_d; # 43981

# Rational
say 1_2_3_4.2_5; # 1234.25

# Rational in exponential notation
say 6.0_22e4; # 60220

# Apart from starting the number with an underscore, can be placed anywhere in the number.

say 1234_.25;       # 1234.25
say 1234._25;       # 1234.25
say 1234.25_;       # 1234.25
say 12__34.25;      # 1234.25
# say _1234.25;     # syntax error
```