To get the number of unique values in a pandas DataFrame or Series, the simplest way is to use the pandas **nunique()** function.

`df["variable"].nunique()`

When working with data as a data science or data analyst, it’s important to be able to find the basic descriptive statistics of a set of data.

One basic descriptive statistic which is important is the number of unique values in a dataset.

To get the number of unique values in a DataFrame, we can use the pandas **nunique()** function.

The following code will get you the count of unique values of a series in Python:

`df["variable"].nunique()`

If you want to get the number of unique values of an entire DataFrame in pandas, you can call **nunique()** in the following way:

`df.nunique()`

## Getting the Count of Unique Values of All Columns in DataFrame Using Pandas

Let’s say I have the following pandas DataFrame:

```
Name Weight_Change Month
0 Jim -16.20 1
1 Sally 12.81 1
2 Bob -20.45 1
3 Sue 15.35 1
4 Jill -12.43 1
5 Larry -18.52 1
6 Jim -6.10 2
7 Sally -2.81 2
8 Bob 12.45 2
9 Sue -0.32 2
10 Jill -1.23 2
11 Larry -8.52 2
12 Jim 5.20 3
13 Sally 12.81 3
14 Bob -2.45 3
15 Sue 5.35 3
16 Jill -2.43 3
17 Larry -1.85 3
```

We can call the **nunique** function on the DataFrame to get the number of unique values for all of the columns.

```
print(df.nunique())
Name 6
Weight_Change 18
Month 3
dtype: int64
```

## Getting the Count of Unique Values of a Column Using Pandas

Let’s say we only want to get the count of unique values of a single column in a pandas DataFrame.

In the DataFrame above, let’s get the count of unique values for the column “Month”, and the column “Name”. We should expect 3 and 6, respectively.

To get the count of unique values, I can do the following in my python code:

```
print(df["Month"].nunique())
print(df["Name"].nunique())
#Output:
3
6
```

Hopefully this article has been useful for you to find the number of unique values in a pandas DataFrame using Python.

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