How to split a Python list into evenly sized chunks Last Updated : 04 Jun, 2024 Comments Improve Suggest changes Like Article Like Report Iteration in Python is repeating a set of statements until a certain condition is met. This is usually done using a for loop or a while loop. There are several ways to split a Python list into evenly sized-chunks. Here are the 5 main methods: Method 1: Using a Loop with List SlicingUse for loop along with list slicing to iterate over chunks of a list. Python def chunked_list(lst, chunk_size): for i in range(0, len(lst), chunk_size): yield lst[i:i + chunk_size] if __name__ == "__main__": lst = [1, 2, 3, 4, 5, 6, 7, 8, 9] chunk_size = 3 for chunk in chunked_list(lst, chunk_size): print(chunk) Output[1, 2, 3] [4, 5, 6] [7, 8, 9] Method 2: Using List Comprehension with range()You can also use a list comprehension with range() to create the chunks and then iterate over them. This is the one line code rather than using yield. Python lst = [1, 2, 3, 4, 5, 6, 7, 8, 9] chunk_size = 3 chunks = [lst[i:i + chunk_size] for i in range(0, len(lst), chunk_size)] for chunk in chunks: print(chunk) Output[1, 2, 3] [4, 5, 6] [7, 8, 9] Method 3: Using itertools.islice()You can also use islice function, which is provided by the the itertools module. It is used to create an iterator that returns selected elements from the iterable. Python from itertools import islice def chunked_list(lst, chunk_size): it = iter(lst) while True: chunk = list(islice(it, chunk_size)) if not chunk: break yield chunk if __name__ == "__main__": lst = [1, 2, 3, 4, 5, 6, 7, 8, 9] chunk_size = 3 for chunk in chunked_list(lst, chunk_size): print(chunk) Output[1, 2, 3] [4, 5, 6] [7, 8, 9] Method 4: Using NumPy (for large arrays/lists)While, you will be dealing with large lists or need high performance, using numpy is the best idea. Python import numpy as np def chunked_list(lst, chunk_size): return np.array_split(lst, np.ceil(len(lst) / chunk_size)) if __name__ == "__main__": lst = [1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15,16,17,18] chunk_size = 4 chunks = chunked_list(lst, chunk_size) for chunk in chunks: print(chunk) Output[1 2 3 4] [5 6 7 8] [ 9 10 11 12] [13 14 15] [16 17 18] Method 5: Using a Generator FunctionThis Generator method is similar to list comprehension but more memory-efficient as it yields chunks one at a time. Python def chunked_list(list_data,chunk_size): for i in range(0,len(list_data),chunk_size): yield list_data[i:i + chunk_size] if __name__ == "__main__": lst = [11,12,13,14,15,16,17,18,19,20,21,22] chunk_size = 3 for chunk in chunked_list(lst, chunk_size): print(chunk) Output[11, 12, 13] [14, 15, 16] [17, 18, 19] [20, 21, 22] Comment More infoAdvertise with us Next Article How to split a Python list into evenly sized chunks S somraj210sbk Follow Improve Article Tags : Python Practice Tags : python Similar Reads How to Split a File into a List in Python In this article, we are going to see how to Split a File into a List in Python. When we want each line of the file to be listed at consecutive positions where each line becomes an element in the file, the splitlines() or rstrip() method is used to split a file into a list. 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