How to print a percentage value in python?

Since Python 3.0, str.format and format support a percentage presentation type:

>>> f"{1/3:.0%}"
'33%'
>>> "{:.0%}".format(1/3)
'33%'
>>> format(1/3, ".0%")
'33%'

Percentage. Multiplies the number by 100 and displays in fixed ('f') format, followed by a percent sign.

The .0 part of the format spec .0% indicates that you want zero digits of precision after the decimal point, because with f"{1/3:%}" you would get the string '33.333333%'.

It works with integers, floats, and decimals. See PEP 3101.

There is a way more convenient 'percent'-formatting option for the .format() format method:

>>> '{:.1%}'.format(1/3.0)
'33.3%'

Just for the sake of completeness, since I noticed no one suggested this simple approach:

>>> print("%.0f%%" % (100 * 1.0/3))
33%

Details:

• %.0f stands for "print a float with 0 decimal places", so %.2f would print 33.33
• %% prints a literal %. A bit cleaner than your original +'%'
• 1.0 instead of 1 takes care of coercing the division to float, so no more 0.0

You are dividing integers then converting to float. Divide by floats instead.

As a bonus, use the awesome string formatting methods described here: http://docs.python.org/library/string.html#format-specification-mini-language

To specify a percent conversion and precision.

>>> float(1) / float(3)
[Out] 0.33333333333333331

>>> 1.0/3.0
[Out] 0.33333333333333331

>>> '{0:.0%}'.format(1.0/3.0) # use string formatting to specify precision
[Out] '33%'

>>> '{percent:.2%}'.format(percent=1.0/3.0)
[Out] '33.33%'

A great gem!