Use with AI>>> a = "545.2222"
>>> float(a)
545.22220000000004
>>> int(float(a))
545
Answer from Harley Holcombe on Stack Overflow Top answer 1 of 16
3127
Use with AI>>> a = "545.2222"
>>> float(a)
545.22220000000004
>>> int(float(a))
545
2 of 16
606
Python2 method to check if a string is a float:
Use with AIdef is_float(value):
if value is None:
return False
try:
float(value)
return True
except:
return False
For the Python3 version of is_float see: Checking if a string can be converted to float in Python
A longer and more accurate name for this function could be: is_convertible_to_float(value)
What is, and is not a float in Python may surprise you:
The below unit tests were done using python2. Check it that Python3 has different behavior for what strings are convertable to float. One confounding difference is that any number of interior underscores are now allowed: (float("1_3.4") == float(13.4)) is True
val is_float(val) Note
-------------------- ---------- --------------------------------
"" False Blank string
"127" True Passed string
True True Pure sweet Truth
"True" False Vile contemptible lie
False True So false it becomes true
"123.456" True Decimal
" -127 " True Spaces trimmed
"\t\n12\r\n" True whitespace ignored
"NaN" True Not a number
"NaNanananaBATMAN" False I am Batman
"-iNF" True Negative infinity
"123.E4" True Exponential notation
".1" True mantissa only
"1_2_3.4" False Underscores not allowed
"12 34" False Spaces not allowed on interior
"1,234" False Commas gtfo
u'\x30' True Unicode is fine.
"NULL" False Null is not special
0x3fade True Hexadecimal
"6e7777777777777" True Shrunk to infinity
"1.797693e+308" True This is max value
"infinity" True Same as inf
"infinityandBEYOND" False Extra characters wreck it
"12.34.56" False Only one dot allowed
u'四' False Japanese '4' is not a float.
"#56" False Pound sign
"56%" False Percent of what?
"0E0" True Exponential, move dot 0 places
0**0 True 0___0 Exponentiation
"-5e-5" True Raise to a negative number
"+1e1" True Plus is OK with exponent
"+1e1^5" False Fancy exponent not interpreted
"+1e1.3" False No decimals in exponent
"-+1" False Make up your mind
"(1)" False Parenthesis is bad
You think you know what numbers are? You are not so good as you think! Not big surprise.
Don't use this code on life-critical software!
Catching broad exceptions this way, killing canaries and gobbling the exception creates a tiny chance that a valid float as string will return false. The float(...) line of code can failed for any of a thousand reasons that have nothing to do with the contents of the string. But if you're writing life-critical software in a duck-typing prototype language like Python, then you've got much larger problems.
GeeksforGeeks
geeksforgeeks.org › python › convert-string-to-float-in-python
Convert String to Float in Python - GeeksforGeeks
July 15, 2025 - It converts a string into a Decimal object, effectively avoiding common floating-point rounding errors. ... eval() function reads and runs a string as a Python expression. It can turn a numeric string like "33.28" into a float. However, it's risky to use with untrusted input because it can run harmful code.
Python string to float conversion
I don't know what you mean: >>> a = '1721244344.700249000' >>> float(a) 1721244344.700249 These are all the decimal places. Trailing zeros will always be omitted as they are irrelevant. If you want to show them, do so when you output the value: >>> print(a.format("{:.9}")) 1721244344.700249000 More on reddit.com
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July 29, 2024How to convert string to float in Python? Why is it a float when directly assigned but a string when a user inputs it? - Stack Overflow
My program prompts the user to input the volume of a sphere. This is one of the example input I have to try: 1.4*1.0e6 This is what I have as the prompt right now: volume = float(input("Enter More on stackoverflow.com
How to convert string to float ?
a='25$' b=float(''.join([i for i in a if i.isdigit()])) print(b) Use list iteration to take the digits and join the elements in the new list and convert to float value. More on reddit.com
42
69
November 14, 2022How I convert float to string in this case?
You shouldn't call your variable sum, as that's a name of a built in function: https://docs.python.org/3/library/functions.html#sum Your problem however, stems from trying to add a string to a float. Could you please tell me, what is Adam + 5? Well, you can't, because it makes no mathematical sense. You didn't save the string representation str(sum), so sum never changed to a string What your research found is f-strings and they are very easy to use. Try: print(f"the sum of the values is {sum}") Simply, put an f before a string starts, then any string that you want goes between " and ", while any variables or other values go between { and } More on reddit.com
4
2
August 21, 202202:33
How to parse a string to a float or int in Python - YouTube
00:55
Convert string to float in python | String to float datatype ...
08:37
Python Program #58 - Convert a String to a Float or Int in Python ...
Python Program to Parse a String to a Float or Integer using ...
ValueError: could not convert string to float - YouTube
Python convert string to float
DigitalOcean
digitalocean.com › community › tutorials › python-convert-string-to-float
How to Convert String to Float in Python: Complete Guide with Examples | DigitalOcean
July 10, 2025 - Learn how to convert strings to floats in Python using float(). Includes syntax, examples, error handling tips, and real-world use cases for data parsing.
IONOS
ionos.com › digital guide › websites › web development › converting python strings to floats
How to convert Python strings to floats - IONOS
February 1, 2025 - In programs that work with various kinds of data, float() is used to ensure that data remains consistent by converting values into a numerical format. To convert Python strings to floats, use float() and enter a valid string as the argument:
Reddit
reddit.com › r/learnpython › python string to float conversion
r/learnpython on Reddit: Python string to float conversion
July 29, 2024 -
Hi all, I have a string a = '1721244344.700249000', I want to convert it to a floating value.
Float() is returning only 2 places after decimal point. Like 1721244344.7
Is there a way I can convert the entire string to a floating point value and get all the decimal (upto 9 places after decimal point)?
I have to use python v2.7 for this.
Edit: I do not have problem in printing the all 9 decimal places but I need the floating value so that I can subtract another value so that I get the difference with accuracy upto 9 th decimal point.
Top answer 1 of 5
7
I don't know what you mean: >>> a = '1721244344.700249000' >>> float(a) 1721244344.700249 These are all the decimal places. Trailing zeros will always be omitted as they are irrelevant. If you want to show them, do so when you output the value: >>> print(a.format("{:.9}")) 1721244344.700249000
2 of 5
3
I have to use python v2.7 for this. ?????????!
Cherry Servers
cherryservers.com › home › blog › python › how to convert string to float in python (6 different ways)
How to Convert String to Float in Python (6 Different Ways) | Cherry Servers
February 10, 2026 - ... Using the float() function is the most common way to convert string to float in Python. What’s more, it is a built-in function which means it comes with standard Python installation.
Mimo
mimo.org › tutorials › python › how-to-convert-string-to-float-in-python
How to Convert String to Float in Python
Use float("3.14") to convert a numeric string to a float. Clean the string first for spaces and separators, then convert. Wrap conversion in try/except ValueError for messy input.
Sentry
sentry.io › sentry answers › python › how do i parse a string to a float or int?
Python: How to Parse a String to a Float or Int | Sentry
September 11, 2026 - Convert a string to a float or int in Python using the float() and int() built-ins, with error handling for strings that aren't cleanly numeric
Jeremy Morgan
jeremymorgan.com › python › how-to-convert-a-string-to-a-float-in-python
How to Convert a String to a Float in Python - Jeremy Morgan's
December 9, 2023 - The eval() function can be dangerous if used with untrusted input, as it can execute any Python code contained in the string. Therefore, it is recommended to use the float() function for converting strings to floats whenever possible.
W3Schools
w3schools.com › python › python_casting.asp
Python Casting
Python is an object-orientated language, and as such it uses classes to define data types, including its primitive types. Casting in python is therefore done using constructor functions: int() - constructs an integer number from an integer literal, a float literal (by removing all decimals), or a string literal (providing the string represents a whole number)
iO Flood
ioflood.com › blog › convert-string-to-float-python
Convert a String to a Float in Python: 3 Easy Methods
December 11, 2023 - So, let’s dive into to String conversion in Python! You can convert a string to a float in Python using the float() function and the syntax, number = float(data).
PhoenixNAP
phoenixnap.com › home › kb › devops and development › python: string to float conversion
Python: String to Float Conversion | phoenixNAP KB
April 29, 2026 - Note: Check out our in-depth article to learn more about Python data types. The float() function is the simplest and most direct way to convert a string into a float.
Scaler
scaler.com › home › topics › how to convert string to float in python?
Convert String to Float in Python - Scaler Topics
May 5, 2022 - The first step in using NumPy to convert a string to a float is to import the NumPy library, which would be used to convert the string to the float values. Later, you can convert the string to a floating-point value in Python using the astype method, which is an in-built technique.
Top answer 1 of 3
5
For converting a string to float you can use float(). Eg.float('1.2123') You can not convert '*' into float because its an operator that's why error is coming.
#observe the code
volume = float(input("Enter volume of sphere in mm^3: "))
input() = Takes input from user and stores it in string
float() = It is used to convert strings to float
Your code is volume = float(input("Enter volume of sphere in mm^3: "))
1st input() takes input from user in string then float() converts it into float.
But a = 1.4*1.0e6 there is no input() function involved thats why it's a float.
You can simply achieve your work by
volume = eval(input("Enter volume of sphere in mm^3: "))
OR
volume = input("Enter volume of sphere in mm^3: ").split("*")
volume = float(volume[0])*float(volume[1])
split(separator)- It splits a string into an array of sub-strings, by a separator string provided by user
You can read about eval from here:- Read abut eval() from here
2 of 3
-1
ValueError: could not convert string to float: '1.4*1.0e6'
you try to convert formula to float. the most easy way is convert string to formula using eval
volume = eval(input("Enter volume of sphere in mm^3: "))
Centron
centron.de › home › tutorials › how to convert a string to a float in python
How To Convert a String to a Float in Python – centron
August 25, 2026 - This tutorial was tested with Python 3.9.6. We can convert a string to float in Python using the float() function. This is a built-in function used to convert an object to a floating point number.
Reddit
reddit.com › r/learnpython › how to convert string to float ?
r/learnpython on Reddit: How to convert string to float ?
November 14, 2022 -
For example if i input 25$ i want the output to be 25.00 Or input 50% output 0.50
Top answer 1 of 13
13
Use regexes if your string format can vary. If you always want to cut off the last character, use string sunsetting. [Edit: string subsetting]
2 of 13
4
a='25$' b=float(''.join([i for i in a if i.isdigit()])) print(b) Use list iteration to take the digits and join the elements in the new list and convert to float value.
Medium
medium.com › @ryan_forrester_ › converting-strings-to-floats-in-python-a-complete-guide-f0ec19bf30a0
Converting Strings to Floats in Python: A Complete Guide | by ryan | Medium
October 28, 2024 - The `float()` function handles both regular decimal numbers and scientific notation. It’s worth noting that Python uses dots (.) rather than commas (,) as decimal separators. Real-world data often comes in various formats. Here’s how to handle them: # Removing currency symbols price_string = "$99.99" price = float(price_string.replace("$", "")) print(price) # Output: 99.99 # Converting percentage strings percentage = "85.5%" decimal = float(percentage.strip("%")) / 100 print(decimal) # Output: 0.855 # Handling thousand separators large_number = "1,234,567.89" cleaned_number = float(large_number.replace(",", "")) print(cleaned_number) # Output: 1234567.89
Note.nkmk.me
note.nkmk.me › home › python
Convert a String to a Number (int, float) in Python | note.nkmk.me
April 29, 2025 - In Python, you can convert a string (str) to a number using int() for an integer or float() for a floating-point number. Convert a string to int: int() Convert a string to float: float() Convert a bin ...
Python Guides
pythonguides.com › convert-string-to-float-in-python
Convert String to Float in Python (Commas, ValueError Fix)
September 22, 2026 - To convert a string to a float in Python, pass it to float(): float("19.99") returns 19.99. If the string contains thousands separators, remove them first (float("1,234.5".replace(",", ""))), and wrap the call in try/except ValueError when the ...
Medium
medium.com › @Doug-Creates › convert-string-to-float-or-int-in-python-0d93ce89d7b1
Convert String to Float or Int in Python | by Doug Creates | Medium
March 24, 2024 - Parsing a string to a float or int involves checking the string format, attempting conversion to float or int based on its content, handling potential errors, and using Python’s built-in functions like float() and int() for conversion, ensuring data type compatibility and error-free conversion.