It's the corrected sample standard deviation.
You can convince yourself of this with a simple Series and applying the formulae:

In [11]: s = pd.Series([1, 2])

In [12]: s.std()
Out[12]: 0.70710678118654757

In [13]: from math import sqrt
   ....:  sqrt(0.5)
Out[13]: 0.7071067811865476

and the formula for corrected sample standard deviation:

In [14]: sqrt(1./(len(s)-1) * ((s - s.mean()) ** 2).sum())
Out[14]: 0.7071067811865476
Answer from Andy Hayden on Stack Overflow
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Pandas
pandas.pydata.org › docs › reference › api › pandas.DataFrame.describe.html
pandas.DataFrame.describe — pandas 3.0.1 documentation
>>> df.describe(include="all") categorical numeric object count 3 3.0 3 unique 3 NaN 3 top f NaN a freq 1 NaN 1 mean NaN 2.0 NaN std NaN 1.0 NaN min NaN 1.0 NaN 25% NaN 1.5 NaN 50% NaN 2.0 NaN 75% NaN 2.5 NaN max NaN 3.0 NaN
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Statology
statology.org › home › pandas: how to use describe() for only mean and std
Pandas: How to Use describe() for Only Mean and Std
March 8, 2023 - This tutorial explains how to use the describe() function in pandas to only calculate the mean and standard deviation of variables.
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W3Schools
w3schools.com › python › pandas › ref_df_describe.asp
Pandas DataFrame describe() Method
If the DataFrame contains numerical data, the description contains these information for each column: count - The number of not-empty values. mean - The average (mean) value. std - The standard deviation.
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Pandas
pandas.pydata.org › pandas-docs › stable › reference › api › pandas.DataFrame.std.html
pandas.DataFrame.std — pandas 3.0.1 documentation
The behavior of DataFrame.std with axis=None is deprecated, in a future version this will reduce over both axes and return a scalar To retain the old behavior, pass axis=0 (or do not pass axis).
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Pandas
pandas.pydata.org › pandas-docs › stable › reference › api › pandas.DataFrame.describe.html
pandas.DataFrame.describe — pandas 3.0.2 documentation
>>> df.describe(include="all") categorical numeric object count 3 3.0 3 unique 3 NaN 3 top f NaN a freq 1 NaN 1 mean NaN 2.0 NaN std NaN 1.0 NaN min NaN 1.0 NaN 25% NaN 1.5 NaN 50% NaN 2.0 NaN 75% NaN 2.5 NaN max NaN 3.0 NaN
Find elsewhere
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Pandas
pandas.pydata.org › pandas-docs › version › 0.19.1 › generated › pandas.DataFrame.describe.html
pandas.DataFrame.describe — pandas 0.19.1 documentation
DataFrame.describe(percentiles=None, include=None, exclude=None)[source]¶ · Generate various summary statistics, excluding NaN values. ... For numeric dtypes, it will include: count, mean, std, min, max, and lower, 50, and upper percentiles.
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GeeksforGeeks
geeksforgeeks.org › python-pandas-dataframe-describe-method
Pandas DataFrame describe() Method - GeeksforGeeks
June 12, 2025 - import pandas as pd data = ... column. mean: Average (mean) of the values in the column. std: Standard deviation showing how spread out the values are....
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Sharp Sight
sharpsight.ai › blog › pandas-describe
Pandas Describe, Explained - Sharp Sight
February 6, 2024 - Here, we’ll use Pandas describe on an entire dataframe. By default, this will return summary statistics for all of the numeric variables. ... survived pclass age sibsp parch fare count 891.000000 891.000000 714.000000 891.000000 891.000000 891.000000 mean 0.383838 2.308642 29.699118 0.523008 0.381594 32.204208 std 0.486592 0.836071 14.526497 1.102743 0.806057 49.693429 min 0.000000 1.000000 0.420000 0.000000 0.000000 0.000000 25% 0.000000 2.000000 20.125000 0.000000 0.000000 7.910400 50% 0.000000 3.000000 28.000000 0.000000 0.000000 14.454200 75% 1.000000 3.000000 38.000000 1.000000 0.000000 31.000000 max 1.000000 3.000000 80.000000 8.000000 6.000000 512.329200
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Note.nkmk.me
note.nkmk.me › home › python › pandas
pandas: Get summary statistics for each column with describe() | note.nkmk.me
January 20, 2024 - std: Sample standard deviation · min: Minimum Value · max: Maximum Value · 50%: Median (50th percentile) 25%, 75%: 25th and 75th percentiles · Specify percentiles to calculate in describe(): percentiles · For datetime64[ns] type · The ...
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Machine Learning Plus
machinelearningplus.com › blog › pandas describe
Pandas Describe - machinelearningplus
March 8, 2022 - The pandas.describe function is used to get a descriptive statistics summary of a given dataframe. This includes mean, count, std deviation, percentiles, and min-max values of all the features.
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Javatpoint
javatpoint.com › pandas-dataframe-describe
Pandas DataFrame.describe() - javatpoint
Pandas Series.std() Series.to_frame() Series.unique() Series.value_counts() Pandas DataFrame · DataFrame.append() DataFrame.apply() DataFrame.aggregate() DataFrame.assign() DataFrame.astype() DataFrame.count() DataFrame.cut() DataFrame.describe() DataFrame.drop_duplicates() DataFrame.groupby() DataFrame.head() DataFrame.hist() DataFrame.iterrows() DataFrame.join() DataFrame.mean() DataFrame.melt() DataFrame.merge() DataFrame.pivot_table() DataFrame.query() DataFrame.rename() DataFrame.sample() DataFrame.shift() DataFrame.sort() DataFrame.sum() DataFrame.to_excel() DataFrame.transform() DataFrame.transpose() DataFrame.where() Add column to DataFrame columns ·
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Arab Psychology
scales.arabpsychology.com › home › how can i use the describe() function in pandas to only calculate the mean and standard deviation of my data?
How Can I Use The Describe() Function In Pandas To Only Calculate The Mean And Standard Deviation Of My Data?
June 24, 2024 - ‘std’]. This will limit the output of the describe() function to only the mean and standard deviation of your data, providing a concise summary of these two important measures.
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CodeFatherTech
codefather.tech › home › blog › pandas standard deviation: analyse your data with python
Pandas Standard Deviation: Analyse Your Data With Python
June 22, 2025 - The Pandas DataFrame std() function allows to calculate the standard deviation of a data set. The standard deviation is usually calculated for a given column and it’s normalised by N-1 by default.
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W3Schools
w3schools.com › python › pandas › ref_df_std.asp
Pandas DataFrame std() Method
import pandas as pd data = [[10, 18, 11], [13, 15, 8], [9, 20, 3]] df = pd.DataFrame(data) print(df.std()) Try it Yourself » · The std() method calculates the standard deviation for each column.
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GeeksforGeeks
geeksforgeeks.org › python › python-pandas-dataframe-std
Python | Pandas dataframe.std() - GeeksforGeeks
October 22, 2019 - Python is a great language for ... and analyzing data much easier. Pandas dataframe.std() function return sample standard deviation over requested axis....