Big byte-order is like the usual decimal notation, but in base 256:
230 * 256**3 + 4 * 256**2 + 0 * 256**1 + 0 * 256**0 = 3859021824
just like
1234 = 1 * 10**3 + 2 * 10**2 + 3 * 10**1 + 4 * 10**0
For little byte-order, the order is reversed:
0 * 256**3 + 0 * 256**2 + 4 * 256**1 + 230 = 1254
Python
docs.python.org › 3 › builtins › stdtypes.html
Built-in Types — Python 3.14.7 documentation
Changed in version 3.11: Added default argument values for length and byteorder. classmethod int.from_bytes(bytes, byteorder='big', *, signed=False)¶
GeeksforGeeks
geeksforgeeks.org › python › how-to-convert-bytes-to-int-in-python
How to Convert Bytes to Int in Python? - GeeksforGeeks
July 23, 2025 - Converting bytes to integers in ... it can be converted to the integer 1. int.from_bytes() method is used to convert a byte object into an integer....
python - How is int.from_bytes() calculated? - Stack Overflow
I am trying to understand what from_bytes() actually does. The documentation mention this: The byteorder argument determines the byte order used to represent the integer. If byteorder is "big", ... More on stackoverflow.com
python - Convert bytes to int? - Stack Overflow
I'm currently working on an ... convert bytes to an integer. I know that: ... Yet I cannot find out how to do the inverse. What am I doing terribly wrong? ... There is also the struct module if you want to convert multiple variables at once. ... Possible duplicate of Reading integers from binary file ... More on stackoverflow.com
int.to_bytes and int.from_bytes implementations incomplete
These methods have the following comments in them: // TODO: Support long ints // TODO: Support byteorder param // TODO: Support signed param I encountered this when trying to convert an int to big-endian bytes, but to_bytes returned litt... More on github.com
13
June 11, 2014bytes -> int
You have to choose the right sizes for the data types and pad the slices with zero bytes: bytes1 := []byte{84, 48, 92, 0} // 4 bytes = 32 bits bytes2 := []byte{84, 48, 92, 91, 244, 0, 0, 0} // 8 bytes = 64 bits num1 := int(binary.LittleEndian.Uint32(bytes1)) fmt.Println("num1:", num1) num2 := int(binary.LittleEndian.Uint64(bytes2)) fmt.Println("num2:", num2) More on reddit.com
2
8
July 6, 2023How To Convert Int To Byte In Java - YouTube
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Size of int variable 2 or 4 bytes - YouTube
03:02
byte + byte = int… why - must watch - YouTube
TutorialsPoint
tutorialspoint.com › article › how-to-convert-bytes-to-int-in-python
How to Convert Bytes to Int in Python?
March 27, 2026 - By converting bytes to integers, we can perform various arithmetic and logical operations, interpret data, and manipulate it as needed. The int.from_bytes() method is the standard way to create an integer from a sequence of bytes.
Top answer 1 of 8
305
Assuming you're on at least 3.2, there's a built in for this:
int.from_bytes(bytes,byteorder, *,signed=False)...
The argument
bytesmust either be a bytes-like object or an iterable producing bytes.The
byteorderargument determines the byte order used to represent the integer. Ifbyteorderis"big", the most significant byte is at the beginning of the byte array. Ifbyteorderis"little", the most significant byte is at the end of the byte array. To request the native byte order of the host system, usesys.byteorderas the byte order value.The
signedargument indicates whether two’s complement is used to represent the integer.
## Examples:
int.from_bytes(b'\x00\x01', "big") # 1
int.from_bytes(b'\x00\x01', "little") # 256
int.from_bytes(b'\x00\x10', byteorder='little') # 4096
int.from_bytes(b'\xfc\x00', byteorder='big', signed=True) #-1024
2 of 8
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Lists of bytes are subscriptable (at least in Python 3.6). This way you can retrieve the decimal value of each byte individually.
>>> intlist = [64, 4, 26, 163, 255]
>>> bytelist = bytes(intlist) # b'@\x04\x1a\xa3\xff'
>>> for b in bytelist:
... print(b) # 64 4 26 163 255
>>> [b for b in bytelist] # [64, 4, 26, 163, 255]
>>> bytelist[2] # 26
AskPython
askpython.com › python › built-in-methods › python-bit-functions
Python Bit Functions for Integer Data [With Easy Explanation] - AskPython
February 16, 2023 - That is, from_bytes() function takes an array of bytes as an argument along with the byteorder parameter and then returns the integer value corresponding to it.
GitHub
github.com › micropython › micropython › issues › 682
int.to_bytes and int.from_bytes implementations incomplete · Issue #682 · micropython/micropython
June 11, 2014 - I encountered this when trying to convert an int to big-endian bytes, but to_bytes returned little-endian bytes instead. from_bytes also apparently only supports little-endian bytes.
Author: micropython
GeeksforGeeks
geeksforgeeks.org › python › python-bit-functions-on-int-bit_length-to_bytes-and-from_bytes
Python bit functions on int (bit_length, to_bytes and from_bytes) - GeeksforGeeks
August 20, 2020 - # Returns integer value of '\x00\x10' in big endian machine. print(int.from_bytes(b'\x00\x10', byteorder ='big'))
Reddit
reddit.com › r/golang › bytes -> int
r/golang on Reddit: bytes -> int
July 6, 2023 -
Hi,I am trying to rewrite some python lines to golang and I am stuck on converting byte array to int (little-endian byteorder)
python:
bytes1 = [84, 48, 92]bytes2 = [84, 48, 92, 91, 244]num1 = int.from_bytes(bytes1, "little")print(f"num1: ", num1)num2 = int.from_bytes(bytes2, "little")print(f"num2: ", num2)
gives me output:
num1: 6041684
num2: 1049504788564
and in golang :
`bytes1 := []byte{84, 48, 92}`
`bytes2 := []byte{84, 48, 92, 91, 244}`
`num1 := int(binary.LittleEndian.Uint16(bytes1))`
`fmt.Println("num1:", num1)`
`num2 := int(binary.LittleEndian.Uint32(bytes2))`
`fmt.Println("num2:", num2)`
I get:
num1: 12372
num2: 1532768340
can someone tell me what am I doing wrong ?
Bobby Hadz
bobbyhadz.com › blog › convert-int-to-bytes-in-python
How to convert Int to Bytes and Bytes to Int in Python | bobbyhadz
The int.from_bytes() method returns the integer represented by the given byte array.
Python.org
discuss.python.org › ideas
Proposal: int.from_bytes and int.to_bytes, but for buffers - Ideas - Discussions on Python.org
August 20, 2026 - Right now you have to take a slice before passing any data to int.from_bytes if you want to parse int at a certain offset. Which is extra allocations, even if it is something as cheap as memoryview. The same goes for int.to_bytes, it allocates bytes every time.
Google Sites
sites.google.com › site › pythonpasapas › methodes › int › int-from_bytes
Mon Python pas à pas - int ( ).from_bytes ( )
Retourne un int ( ) correspondant au tableau d'octets, de type bytes ( ) ou bitearray ( ), spécifié.
Microsoft Learn
learn.microsoft.com › en-us › dotnet › csharp › programming-guide › types › how-to-convert-a-byte-array-to-an-int
How to convert a byte array to an int - C# | Microsoft Learn
This example shows you how to use the BitConverter class to convert an array of bytes to an int and back to an array of bytes. You may have to convert from bytes to a built-in data type after you read bytes off the network, for example.
Finxter
blog.finxter.com › home › learn python blog › 5 best ways to convert python bytes to int
5 Best Ways to Convert Python Bytes to Int - Be on the Right Side of Change
February 23, 2024 - The challenge is to convert this byte data, possibly b'\x00\x10', to its integer equivalent, 16. Python’s built-in method int.from_bytes() allows for straightforward conversion of bytes to an integer.
Raspberry Pi Forums
forums.raspberrypi.com › board index › programming › python
how to convert an integer to byte(s) in python? - Raspberry Pi Forums
November 15, 2017 - bytestring = b'\xb4' value = int.from_bytes(bytestring, 'little') I wouldnt use readline() to read raw binary, it will get confused if the data is 13 (it will treat that as being the carriage return character).
GitHub
github.com › micropython › micropython › blob › master › tests › basics › int_bytes.py
micropython/tests/basics/int_bytes.py at master · micropython/micropython
print((-100).to_bytes(10, "big", signed=True)) print(int.from_bytes(b"\0\0\0\0\0\0\0\0\0\x01", "big")) print(int.from_bytes(b"\x01\0", "big")) · # negative number of bytes should raise an error · try: (1).to_bytes(-1, "little") except ValueError: print("ValueError") ·
Author: micropython
Real Python
realpython.com › python-bytes
Bytes Objects: Handling Binary Data in Python – Real Python
March 5, 2025 - For example, you derive -42 by first taking the binary representation of 42, which is 00000000 00101010, inverting the bits, and then adding one to get 11111111 11010110. The resulting bit pattern corresponds to two bytes, 255 and 214 in decimal, which encode the value -42 in two’s complement. Later, you restore one of the binary words to its original form by using int.from_bytes() and specifying matching argument values.
GeeksforGeeks
geeksforgeeks.org › python › to-bytes-in-python
.to_bytes() in Python - GeeksforGeeks
December 18, 2025 - Explanation: num.to_bytes(2, 'little') converts integer 10 into 2 bytes using little-endian order.
Python.org
discuss.python.org › core development
What should be the default value for `int.to_bytes(..., byteorder=?, ...)` - Core Development - Discussions on Python.org
September 13, 2021 - Over in bpo-45155 and this PR there is a discussion about adding default arguments to int.to_bytes() and int.from_bytes() in order to make the former easier to use to create single byte bytes objects: >>> (65).to_bytes() b'A' The shedding centers around what the default value should be for ...
Python.org
discuss.python.org › python help
Int to bytes conversion confusion - Python Help - Discussions on Python.org
February 8, 2021 - I am trying to convert an integer to bytes and am confused about what is happening. If I do this: x=b’1’ I get: print(x) b’1’ However, when I do this: y=1 x=bytes(y) I get: print(x) b’\x01’ When I try to write…