How to change the figure size of a seaborn axes or figure level plot

You can also set figure size by passing dictionary to rc parameter with key 'figure.figsize' in seaborn set_theme method (which replaces the set method, deprecated in v0.11.0 (September 2020))

import seaborn as sns

sns.set_theme(rc={'figure.figsize':(11.7,8.27)})

Other alternative may be to use figure.figsize of rcParams to set figure size as below:

from matplotlib import rcParams

# figure size in inches
rcParams['figure.figsize'] = 11.7,8.27

More details can be found in matplotlib documentation

You need to create the matplotlib Figure and Axes objects ahead of time, specifying how big the figure is:

from matplotlib import pyplot
import seaborn

import mylib

a4_dims = (11.7, 8.27)
df = mylib.load_data()
fig, ax = pyplot.subplots(figsize=a4_dims)
seaborn.violinplot(ax=ax, data=df, **violin_options)

first import matplotlib and use it to set the size of the figure

from matplotlib import pyplot as plt
import seaborn as sns

plt.figure(figsize=(15,8))
ax = sns.barplot(x="Word", y="Frequency", data=boxdata)

You can set the context to be poster or manually set fig_size.

import numpy as np
import seaborn as sns
import matplotlib.pyplot as plt

np.random.seed(0)
n, p = 40, 8
d = np.random.normal(0, 2, (n, p))
d += np.log(np.arange(1, p + 1)) * -5 + 10


# plot
sns.set_style('ticks')
fig, ax = plt.subplots()
# the size of A4 paper
fig.set_size_inches(11.7, 8.27)
sns.violinplot(data=d, inner="points", ax=ax)    
sns.despine()

fig.savefig('example.png')