A simple example which encodes an array using LabelEncoder, OneHotEncoder, LabelBinarizer is shown below.

I see that OneHotEncoder needs data in integer encoded form first to convert into its respective encoding which is not required in the case of LabelBinarizer.

from numpy import array
from sklearn.preprocessing import LabelEncoder
from sklearn.preprocessing import OneHotEncoder
from sklearn.preprocessing import LabelBinarizer

# define example
data = ['cold', 'cold', 'warm', 'cold', 'hot', 'hot', 'warm', 'cold', 
'warm', 'hot']
values = array(data)
print "Data: ", values
# integer encode
label_encoder = LabelEncoder()
integer_encoded = label_encoder.fit_transform(values)
print "Label Encoder:" ,integer_encoded

# onehot encode
onehot_encoder = OneHotEncoder(sparse=False)
integer_encoded = integer_encoded.reshape(len(integer_encoded), 1)
onehot_encoded = onehot_encoder.fit_transform(integer_encoded)
print "OneHot Encoder:", onehot_encoded

#Binary encode
lb = LabelBinarizer()
print "Label Binarizer:", lb.fit_transform(values)

Another good link which explains the OneHotEncoder is: Explain onehotencoder using python

There may be other valid differences between the two which experts can probably explain.

Answer from Rahul Pant on Stack Overflow
Top answer
1 of 5
46

A simple example which encodes an array using LabelEncoder, OneHotEncoder, LabelBinarizer is shown below.

I see that OneHotEncoder needs data in integer encoded form first to convert into its respective encoding which is not required in the case of LabelBinarizer.

from numpy import array
from sklearn.preprocessing import LabelEncoder
from sklearn.preprocessing import OneHotEncoder
from sklearn.preprocessing import LabelBinarizer

# define example
data = ['cold', 'cold', 'warm', 'cold', 'hot', 'hot', 'warm', 'cold', 
'warm', 'hot']
values = array(data)
print "Data: ", values
# integer encode
label_encoder = LabelEncoder()
integer_encoded = label_encoder.fit_transform(values)
print "Label Encoder:" ,integer_encoded

# onehot encode
onehot_encoder = OneHotEncoder(sparse=False)
integer_encoded = integer_encoded.reshape(len(integer_encoded), 1)
onehot_encoded = onehot_encoder.fit_transform(integer_encoded)
print "OneHot Encoder:", onehot_encoded

#Binary encode
lb = LabelBinarizer()
print "Label Binarizer:", lb.fit_transform(values)

Another good link which explains the OneHotEncoder is: Explain onehotencoder using python

There may be other valid differences between the two which experts can probably explain.

2 of 5
31

A difference is that you can use OneHotEncoder for multi column data, while not for LabelBinarizer and LabelEncoder.

from sklearn.preprocessing import LabelBinarizer, LabelEncoder, OneHotEncoder

X = [["US", "M"], ["UK", "M"], ["FR", "F"]]
OneHotEncoder().fit_transform(X).toarray()

# array([[0., 0., 1., 0., 1.],
#        [0., 1., 0., 0., 1.],
#        [1., 0., 0., 1., 0.]])
LabelBinarizer().fit_transform(X)
# ValueError: Multioutput target data is not supported with label binarization

LabelEncoder().fit_transform(X)
# ValueError: bad input shape (3, 2)
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Medium
harshal-soni.medium.com › onehotencoding-vs-labelencoder-vs-pandas-get-dummies-how-and-why-b190dff7a86f
OneHotEncoding vs LabelEncoder vs pandas getdummies — How and Why? | by Harshal Soni | Medium
March 29, 2022 - They are quite similar, except that OneHotEncoder could return a sparse matrix that saves a lot of memory and you won’t really need that in y labels. Even if you have a multi-label multi-class problem, you can use MultiLabelBinarizer for your y labels rather than switching to OneHotEncoder for multi hot encoding
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scikit-learn
scikit-learn.org › stable › modules › generated › sklearn.preprocessing.MultiLabelBinarizer.html
MultiLabelBinarizer — scikit-learn 1.9.1 documentation
OneHotEncoder · Encode categorical features using a one-hot aka one-of-K scheme. Examples · >>> from sklearn.preprocessing import MultiLabelBinarizer >>> mlb = MultiLabelBinarizer() >>> mlb.fit_transform([(1, 2), (3,)]) array([[1, 1, 0], [0, 0, 1]]) >>> mlb.classes_ array([1, 2, 3]) >>> mlb.fit_transform([{'sci-fi', 'thriller'}, {'comedy'}]) array([[0, 1, 1], [1, 0, 0]]) >>> list(mlb.classes_) ['comedy', 'sci-fi', 'thriller'] A common mistake is to pass in a list, which leads to the following issue: >>> mlb = MultiLabelBinarizer() >>> mlb.fit(['sci-fi', 'thriller', 'comedy']) MultiLabelBinar
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Netlify
michael-fuchs-python.netlify.app › 2019 › 06 › 16 › types-of-encoder
Types of Encoder - Michael Fuchs Python
June 16, 2019 - MultiLabelBinarizer basically works something like One Hot Encoding. The difference is that for a given column, a row can contain not only one value but several.
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GeeksforGeeks
geeksforgeeks.org › what-is-the-difference-between-labelbinarizer-vs-onehotencoder
What is the difference between LabelBinarizer vs. ...
April 1, 2024 - Your All-in-One Learning Portal. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions.
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213

There are some cases where LabelEncoder or DictVectorizor are useful, but these are quite limited in my opinion due to ordinality.

LabelEncoder can turn [dog,cat,dog,mouse,cat] into [1,2,1,3,2], but then the imposed ordinality means that the average of dog and mouse is cat. Still there are algorithms like decision trees and random forests that can work with categorical variables just fine and LabelEncoder can be used to store values using less disk space.

One-Hot-Encoding has the advantage that the result is binary rather than ordinal and that everything sits in an orthogonal vector space. The disadvantage is that for high cardinality, the feature space can really blow up quickly and you start fighting with the curse of dimensionality. In these cases, I typically employ one-hot-encoding followed by PCA for dimensionality reduction. I find that the judicious combination of one-hot plus PCA can seldom be beat by other encoding schemes. PCA finds the linear overlap, so will naturally tend to group similar features into the same feature.

2 of 4
58

While AN6U5 has given a very good answer, I wanted to add a few points for future reference. When considering One Hot Encoding(OHE) and Label Encoding, we must try and understand what model you are trying to build. Namely the two categories of model we will be considering are:

  1. Tree Based Models: Gradient Boosted Decision Trees and Random Forests.
  2. Non-Tree Based Models: Linear, kNN or Neural Network based.

Let's consider when to apply OHE and when to apply Label Encoding while building tree based models.

We apply OHE when:

  1. When the values that are close to each other in the label encoding correspond to target values that aren't close (non-linear data).
  2. When the categorical feature is not ordinal (dog, cat, mouse).

We apply Label encoding when:

  1. The categorical feature is ordinal (Jr. kg, Sr. kg, Primary school, high school, etc).
  2. When we can come up with a label encoder that assigns close labels to similar categories: This leads to less splits in the trees hence reducing the execution time.
  3. When the number of categorical features in the dataset is huge: One-hot encoding a categorical feature with huge number of values can lead to (1) high memory consumption and (2) the case when non-categorical features are rarely used by model. You can deal with the 1st case if you employ sparse matrices. The 2nd case can occur if you build a tree using only a subset of features. For example, if you have 9 numeric features and 1 categorical with 100 unique values and you one-hot-encoded that categorical feature, you will get 109 features. If a tree is built with only a subset of features, initial 9 numeric features will rarely be used. In this case, you can increase the parameter controlling size of this subset. In xgboost it is called colsample_bytree, in sklearn's Random Forest max_features.

In case you want to continue with OHE, as @AN6U5 suggested, you might want to combine PCA with OHE.

Let's consider when to apply OHE and Label Encoding while building non tree based models.

To apply Label encoding, the dependance between feature and target must be linear in order for Label Encoding to be utilised effectively.

Similarly, in case the dependance is non-linear, you might want to use OHE for the same.

Note: Some of the explanation has been referenced from How to Win a Data Science Competition from Coursera.

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Kaggle
kaggle.com › questions-and-answers › 172969
Label_binarize vs LabelBinarizer vs Onehotencoder -What is the difference ? | Kaggle
Birth of question: I'm working on a mutilclass sentiment analysis(positive/negative/neutral) where while I tried to perform one vs all classifier(One vs Rest...
Find elsewhere
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GeeksforGeeks
geeksforgeeks.org › machine learning › one-hot-encoding-vs-label-encoding
One Hot Encoding vs Label Encoding - GeeksforGeeks
January 22, 2026 - Your All-in-One Learning Portal. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions.
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KDnuggets
kdnuggets.com › 2023 › 01 › encoding-categorical-features-multilabelbinarizer.html
Encoding Categorical Features with MultiLabelBinarizer - KDnuggets
January 20, 2023 - In this mini tutorial, you will learn the difference between multi-class and multi-label. Furthermore, we will apply Scikit-Learn’s MultiLabelBinarizer function to convert iterable of iterables and multilabel targets.
Top answer
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1

Both are within one-vs-all scheme when there is a classification task.

LabelBinarizer it turn every variable into binary within a matrix where that variable is indicated as a column. In other words, it will turn a list into a matrix, where the number of columns in the target matrix is exactly as many as unique value in the input set. If your input labels look like [1, 4, 5] the resulting matrix, is a 3 column matrix and each 1, 4, 5 are a column. then if your instances (observations) are either of 1,4,5, it is gonna be indicated (binary) whether that instance correspond to label 1 or 4 or 5.

you use LabelBinarizer to build regular classifier, for example to train a logistic regression and create the response variable you can use

from sklearn.preprocessing import LabelBinarizer
lb = LabelBinarizer()
lb.fit_transform(['yes', 'no', 'no', 'yes'])

the output is

array([[1],
       [0],
       [0],
       [1]])

or if your feature column is ['red', 'red', 'green', 'blue', 'blue']

array([[1, 0, 0],
       [1, 0, 0],
       [0, 1, 0],
       [0, 0, 1],
       [0, 0, 1]])

MultiLabelBinarizer - does the similar thing but when you have multiple lables. when do you have multiple labels ? for example when you are doing mu multiple label classification. Say, you are building a classifier to predict tags for Questions on StackoverFlow. Your data looks like this

   qId              Tag
0   1                       c#
1   2                     python
2   2                 machine_learning
3   2                     pandas
4   2                      nlp

but you have to convert it in a format where you can do machine learning (one row per observation)

qId c# python machine_learning pandas nlp
1 1 0 0 0 0
2 0 1 1 1 1

and you will use

import pandas as pd
from sklearn.preprocessing import MultiLabelBinarizer

question_tags = pd.read_csv("question_tags.csv")
print(question_tags.head())
mlb = MultiLabelBinarizer()
print(mlb.fit_transform(question_tags))

I hope this clear out the differences when it comes to the practice

UPDATE on your case

how do you parse your 15K unique role to get those 3 category or combination ? is it like, seniority, department, role ? if so, shouldn't you make it like

question_tags = [{'Senior', 'Android', 'Engineer'}, {'Senior', 'Asset', 'Manager'}, {'Senior', 'Billing', 'Manager'}] 

and then pass it to the

mlb = MultiLabelBinarizer()
res = pd.DataFrame(mlb.fit_transform(question_tags), columns=mlb.classes_)

and you will end up with

which shows all three are senior, number 2 and 3 are managers and so on ?

UPDATE 2

if you don't have it parse and basically just need to encode each of 15K unique label, you go with binary. For example you have four observation where two of them are senior android engieers.

question_tags = ['Senior Android Engineer','Senior Android Engineer', 'Senior Asset Manager',  'Senior Billing Manager'] 
lb = LabelBinarizer()
pd.DataFrame(lb.fit_transform(question_tags), columns = lb.classes_)

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0

Scikit-learn's LabelBinarizer converts input labels into binary labels, each example belongs to a single class or not.

Scikit-learn's MultiLabelBinarizer converts input labels into multilabel labels, each example can belong to multiple classes.

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Medium
contactsunny.medium.com › label-encoder-vs-one-hot-encoder-in-machine-learning-3fc273365621
Label Encoder vs. One Hot Encoder in Machine Learning | by Sunny Srinidhi | Medium
January 9, 2020 - Label Encoder vs. One Hot Encoder in Machine Learning Originally published here: http://blog.contactsunny.com/data-science/label-encoder-vs-one-hot-encoder-in-machine-learning Update: SciKit has a …
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scikit-learn
scikit-learn.org › dev › modules › generated › sklearn.preprocessing.MultiLabelBinarizer.html
MultiLabelBinarizer — scikit-learn 1.10.dev0 documentation
OneHotEncoder · Encode categorical features using a one-hot aka one-of-K scheme. Examples · >>> from sklearn.preprocessing import MultiLabelBinarizer >>> mlb = MultiLabelBinarizer() >>> mlb.fit_transform([(1, 2), (3,)]) array([[1, 1, 0], [0, 0, 1]]) >>> mlb.classes_ array([1, 2, 3]) >>> mlb.fit_transform([{'sci-fi', 'thriller'}, {'comedy'}]) array([[0, 1, 1], [1, 0, 0]]) >>> list(mlb.classes_) ['comedy', 'sci-fi', 'thriller'] A common mistake is to pass in a list, which leads to the following issue: >>> mlb = MultiLabelBinarizer() >>> mlb.fit(['sci-fi', 'thriller', 'comedy']) MultiLabelBinar
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Analytics Vidhya
analyticsvidhya.com › home › one hot encoding vs label encoding in machine learning
One Hot Encoding vs Label Encoding in Machine Learning
April 23, 2025 - # creating one hot encoder object onehotencoder = OneHotEncoder() # reshape the 1-D country array to 2-D as fit_transform expects 2-D and fit the encoder X = onehotencoder.fit_transform(df.Country.values.reshape(-1, 1)).toarray()
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Medium
medium.com › bycodegarage › encoding-categorical-data-in-machine-learning-def03ccfbf40
Encoding Categorical data in Machine Learning | by Akhil Reddy Mallidi | #ByCodeGarage | Medium
September 6, 2019 - OneHotEncoder of SciKit Learn encodes categorical data by creating Dummy variables for each label in the feature that was passed as an argument. It accepts only Numerical data as input. So the categorical data that needs to be encoded is converted into Numerical type by using LabelEncoder.