933

How does one change the font size for all elements (ticks, labels, title) on a matplotlib plot?

I know how to change the tick label sizes, this is done with:

import matplotlib 
matplotlib.rc('xtick', labelsize=20) 
matplotlib.rc('ytick', labelsize=20)

But how does one change the rest?

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17 Answers 17

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1170

From the matplotlib documentation,

font = {'family' : 'normal',
        'weight' : 'bold',
        'size'   : 22}

matplotlib.rc('font', **font)

This sets the font of all items to the font specified by the kwargs object, font.

Alternatively, you could also use the rcParams update method as suggested in this answer:

matplotlib.rcParams.update({'font.size': 22})

or

import matplotlib.pyplot as plt
plt.rcParams.update({'font.size': 22})

You can find a full list of available properties on the Customizing matplotlib page.

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18 Comments

nice, except it override any fontsize property found on it's way è_é
Where can I find more options for elements like 'family', 'weight', etc.?
Since many people start with import matplotlib.pyplot as plt, you might like to point out that pyplot has rc as well. You can do plt.rc(... without having to change your imports.
For the impatient: The default font size is 10, as in the second link.
@user32882 - not permanently, it's not saved to disk, but I would assume it would change subsequent plots generated in the same code unless the original value is stored and restored, which is no always convenient. You can do something like for label in (ax.get_xticklabels() + ax.get_yticklabels()): label.set_fontsize(22) to affect text size in a single figure.
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648

If you are a control freak like me, you may want to explicitly set all your font sizes:

import matplotlib.pyplot as plt

SMALL_SIZE = 8
MEDIUM_SIZE = 10
BIGGER_SIZE = 12

plt.rc('font', size=SMALL_SIZE)          # controls default text sizes
plt.rc('axes', titlesize=SMALL_SIZE)     # fontsize of the axes title
plt.rc('axes', labelsize=MEDIUM_SIZE)    # fontsize of the x and y labels
plt.rc('xtick', labelsize=SMALL_SIZE)    # fontsize of the tick labels
plt.rc('ytick', labelsize=SMALL_SIZE)    # fontsize of the tick labels
plt.rc('legend', fontsize=SMALL_SIZE)    # legend fontsize
plt.rc('figure', titlesize=BIGGER_SIZE)  # fontsize of the figure title

Note that you can also set the sizes calling the rc method on matplotlib:

import matplotlib

SMALL_SIZE = 8
matplotlib.rc('font', size=SMALL_SIZE)
matplotlib.rc('axes', titlesize=SMALL_SIZE)

# and so on ...
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4 Comments

I tried many of the answers. This one looks the best, at least in Jupyter notebooks. Just copy the above block at the top and customize the three font size constants.
For me the title size didn't work. I used: plt.rc('axes', titlesize=BIGGER_SIZE)
I think you can combine all settings for the same object into one line. E.g., plt.rc('axes', titlesize=SMALL_SIZE, labelsize=MEDIUM_SIZE)
I tried aome answers. This one is the best!
283

If you want to change the fontsize for just a specific plot that has already been created, try this:

import matplotlib.pyplot as plt

ax = plt.subplot(111, xlabel='x', ylabel='y', title='title')
for item in ([ax.title, ax.xaxis.label, ax.yaxis.label] +
             ax.get_xticklabels() + ax.get_yticklabels()):
    item.set_fontsize(20)
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5 Comments

My purpose was to have the font of x-y labels, ticks and the titles to be of different sizes. A modified version of this worked so well for me.
To get the legends as well use ax.legend().get_texts(). Tested on Matplotlib 1.4.
Might need an ax=plt.gca() if the plot was created without defining an axis.
@JamesS. Rather use ax.get_legend().get_texts(), because ax.legend() redraws the whole legend with default parameters on top of returning the value of ax.get_legend().
ax.get_legend().get_texts() returns a list of each item in your legend. So, to change the font size for one of the entries you need to do something like: ax.get_legend().get_texts()[0].set_fontsize(20)
237 
matplotlib.rcParams.update({'font.size': 22})
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1 Comment

In may case this solution works only if I create a first plot, then "update" as suggested, which leads to updated font size for new figures. Maybe the first plot is necessary to initialize rcParams...
88

This answer is for anyone trying to change all the fonts, including for the legend, and for anyone trying to use different fonts and sizes for each thing. It does not use rc (which doesn't seem to work for me). It is perhaps a bit cumbersome but I could not get to grips with any other method, personally.

I have worked out a slightly different, less cluttered approach than my original answer below. It allows any font on your system, even .otf fonts. To have separate fonts for each thing, just write more font_path and font_prop like variables.

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.font_manager as font_manager
import matplotlib.ticker
# Workaround for Matplotlib 2.0.0 log axes bug https://github.com/matplotlib/matplotlib/issues/8017 :
# matplotlib.ticker._mathdefault = lambda x: '\\mathdefault{%s}'%x 

# Set the font properties (can use more variables for more fonts)
font_path = 'C:\Windows\Fonts\AGaramondPro-Regular.otf'
font_prop = font_manager.FontProperties(fname=font_path, size=14)

ax = plt.subplot() # Defines ax variable by creating an empty plot

# Define the data to be plotted
x = np.linspace(0, 10)
y = x + np.random.normal(x)
plt.plot(x, y, 'b+', label='Data points')

for label in (ax.get_xticklabels() + ax.get_yticklabels()):
    label.set_fontproperties(font_prop)
    label.set_fontsize(13) # Size here overrides font_prop

plt.title("Exponentially decaying oscillations", fontproperties=font_prop,
          size=16, verticalalignment='bottom') # Size here overrides font_prop
plt.xlabel("Time", fontproperties=font_prop)
plt.ylabel("Amplitude", fontproperties=font_prop)
plt.text(0, 0, "Misc text", fontproperties=font_prop)

lgd = plt.legend(loc='lower right', prop=font_prop) # NB different 'prop' argument for legend
lgd.set_title("Legend", prop=font_prop)

plt.show()

Original answer

This basically combines ryggyr's answer here with other answers on SO.

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.font_manager as font_manager

# Set the font dictionaries (for plot title and axis titles)
title_font = {'fontname':'Arial', 'size':'16', 'color':'black', 'weight':'normal',
              'verticalalignment':'bottom'} # Bottom vertical alignment for more space
axis_font = {'fontname':'Arial', 'size':'14'}

# Set the font properties (for use in legend)   
font_path = 'C:\Windows\Fonts\Arial.ttf'
font_prop = font_manager.FontProperties(fname=font_path, size=14)

ax = plt.subplot() # Defines ax variable by creating an empty plot

# Set the tick labels font
for label in (ax.get_xticklabels() + ax.get_yticklabels()):
    label.set_fontname('Arial')
    label.set_fontsize(13)

x = np.linspace(0, 10)
y = x + np.random.normal(x) # Just simulates some data

plt.plot(x, y, 'b+', label='Data points')
plt.xlabel("x axis", **axis_font)
plt.ylabel("y axis", **axis_font)
plt.title("Misc graph", **title_font)
plt.legend(loc='lower right', prop=font_prop, numpoints=1)
plt.text(0, 0, "Misc text", **title_font)
plt.show()

By having several font dictionaries, you can choose different fonts/sizes/weights/colours for the various titles, choose the font for the tick labels, and choose the font for the legend, all independently.

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Comments

78

Here is a totally different approach that works surprisingly well to change the font sizes:

Change the figure size!

I usually use code like this:

import matplotlib.pyplot as plt
import numpy as np
fig = plt.figure(figsize=(4,3))
ax = fig.add_subplot(111)
x = np.linspace(0,6.28,21)
ax.plot(x, np.sin(x), '-^', label="1 Hz")
ax.set_title("Oscillator Output")
ax.set_xlabel("Time (s)")
ax.set_ylabel("Output (V)")
ax.grid(True)
ax.legend(loc=1)
fig.savefig('Basic.png', dpi=300)

The smaller you make the figure size, the larger the font is relative to the plot. This also upscales the markers. Note I also set the dpi or dot per inch. I learned this from a posting the AMTA (American Modeling Teacher of America) forum. Example from above code: enter image description here

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6 Comments

To avoid the axis label being cut-off, save figure with the bbox_inches argument fig.savefig('Basic.png', bbox_inches="tight")
What if I am NOT saving the figure? I am plotting in Juypter Notebook and the resulting axis labels get cut-off.
Thanks! Pointing out the dpi settings was extremely helpful to me in preparing printable versions of my plots without having to adjust all the line sizes, font sizes, etc.
To prevent the label cut-off, also in the notebook as @Zythyr asks, you can use plt.tight_layout()
@Zythyr You can use the dpi=XXX argument also in the call of plt.figure(): plt.figure(figsize=(4,3), dpi=300) to achieve the same result without saving
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50

Use plt.tick_params(labelsize=14)

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2 Comments

Thank you for the code snippet, which might provide some limited, immediate help. A proper explanation would greatly improve its long-term value by describing why this is a good solution to the problem, and would make it more useful to future readers with other similar questions. Please edit your answer to add some explanation, including the assumptions you've made.
Doesn't this just change the tick font size?
50

You can use plt.rcParams["font.size"] for setting font_size in matplotlib and also you can use plt.rcParams["font.family"] for setting font_family in matplotlib. Try this example:

import matplotlib.pyplot as plt
plt.style.use('seaborn-whitegrid')

label = [1,2,3,4,5,6,7,8]
x = [0.001906,0.000571308,0.0020305,0.0037422,0.0047095,0.000846667,0.000819,0.000907]
y = [0.2943301,0.047778308,0.048003167,0.1770876,0.532489833,0.024611333,0.157498667,0.0272095]


plt.ylabel('eigen centrality')
plt.xlabel('betweenness centrality')
plt.text(0.001906, 0.2943301, '1 ', ha='right', va='center')
plt.text(0.000571308, 0.047778308, '2 ', ha='right', va='center')
plt.text(0.0020305, 0.048003167, '3 ', ha='right', va='center')
plt.text(0.0037422, 0.1770876, '4 ', ha='right', va='center')
plt.text(0.0047095, 0.532489833, '5 ', ha='right', va='center')
plt.text(0.000846667, 0.024611333, '6 ', ha='right', va='center')
plt.text(0.000819, 0.157498667, '7 ', ha='right', va='center')
plt.text(0.000907, 0.0272095, '8 ', ha='right', va='center')
plt.rcParams["font.family"] = "Times New Roman"
plt.rcParams["font.size"] = "50"
plt.plot(x, y, 'o', color='blue')

Please, see the output:

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Comments

37

Here is what I generally use in Jupyter Notebook:

# Jupyter Notebook settings

from IPython.core.display import display, HTML
display(HTML("<style>.container { width:95% !important; }</style>"))
%autosave 0
%matplotlib inline
%load_ext autoreload
%autoreload 2

from IPython.core.interactiveshell import InteractiveShell
InteractiveShell.ast_node_interactivity = "all"


# Imports for data analysis
import pandas as pd
import matplotlib.pyplot as plt
pd.set_option('display.max_rows', 2500)
pd.set_option('display.max_columns', 500)
pd.set_option('display.max_colwidth', 2000)
pd.set_option('display.width', 2000)
pd.set_option('display.float_format', lambda x: '%.3f' % x)

#size=25
size=15
params = {'legend.fontsize': 'large',
          'figure.figsize': (20,8),
          'axes.labelsize': size,
          'axes.titlesize': size,
          'xtick.labelsize': size*0.75,
          'ytick.labelsize': size*0.75,
          'axes.titlepad': 25}
plt.rcParams.update(params)
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Comments

15

The changes to the rcParams are very granular, most of the time all you want is just scaling all of the font sizes so they can be seen better in your figure. The figure size is a good trick but then you have to carry it for all of your figures. Another way (not purely matplotlib, or maybe overkill if you don't use seaborn) is to just set the font scale with seaborn:

sns.set_context('paper', font_scale=1.4)

DISCLAIMER: I know, if you only use matplotlib then probably you don't want to install a whole module for just scaling your plots (I mean why not) or if you use seaborn, then you have more control over the options. But there's the case where you have the seaborn in your data science virtual env but not using it in this notebook. Anyway, yet another solution.

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Comments

8

Based on the above stuff:

import matplotlib.pyplot as plt
import matplotlib.font_manager as fm

fontPath = "/usr/share/fonts/abc.ttf"
font = fm.FontProperties(fname=fontPath, size=10)
font2 = fm.FontProperties(fname=fontPath, size=24)

fig = plt.figure(figsize=(32, 24))
fig.text(0.5, 0.93, "This is my Title", horizontalalignment='center', fontproperties=font2)

plot = fig.add_subplot(1, 1, 1)

plot.xaxis.get_label().set_fontproperties(font)
plot.yaxis.get_label().set_fontproperties(font)
plot.legend(loc='upper right', prop=font)

for label in (plot.get_xticklabels() + plot.get_yticklabels()):
    label.set_fontproperties(font)
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7

I just wanted to point out that both the Herman Schaaf's and Pedro M Duarte's answers work but you have to do that before instantiating subplots(), these settings will not affect already instantiated objects. I know it's not a brainer but I spent quite some time figuring out why are those answers not working for me when I was trying to use these changes after calling subplots().

For eg:

import matplotlib.pyplot as plt
plt.rcParams.update({'font.size': 6,})
fig, ax = plt.subplots()
#create your plot
plt.show()

or

SMALL_SIZE = 8
MEDIUM_SIZE = 10
BIGGER_SIZE = 12

plt.rc('font', size=SMALL_SIZE)          # controls default text sizes
plt.rc('xtick', labelsize=SMALL_SIZE)    # fontsize of the tick labels
plt.rc('ytick', labelsize=SMALL_SIZE)    # fontsize of the tick labels
fig, ax = plt.subplots()
#create your plot
plt.show()
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6

I totally agree with Prof Huster that the simplest way to proceed is to change the size of the figure, which allows keeping the default fonts. I just had to complement this with a bbox_inches option when saving the figure as a pdf because the axis labels were cut.

import matplotlib.pyplot as plt
plt.figure(figsize=(4,3))
plt.savefig('Basic.pdf', bbox_inches='tight')
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5

This is an extension to Marius Retegan answer. You can make a separate JSON file with all your modifications and than load it with rcParams.update. The changes will only apply to the current script. So

import json
from matplotlib import pyplot as plt, rcParams

s = json.load(open("example_file.json")
rcParams.update(s)

and save this 'example_file.json' in the same folder.

{
  "lines.linewidth": 2.0,
  "axes.edgecolor": "#bcbcbc",
  "patch.linewidth": 0.5,
  "legend.fancybox": true,
  "axes.color_cycle": [
    "#348ABD",
    "#A60628",
    "#7A68A6",
    "#467821",
    "#CF4457",
    "#188487",
    "#E24A33"
  ],
  "axes.facecolor": "#eeeeee",
  "axes.labelsize": "large",
  "axes.grid": true,
  "patch.edgecolor": "#eeeeee",
  "axes.titlesize": "x-large",
  "svg.fonttype": "path",
  "examples.directory": ""
}
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1 Comment

Or using matplotlib's styling, which is very similar to your idea: matplotlib.org/stable/tutorials/introductory/customizing.html
4

It is mentioned in a comment but deserves its own answer:

Modify both figsize= and dpi= in conjunction to adjust the figure size and the scale of all text labels:

fig, ax = plt.subplots(1, 1, figsize=(8, 4), dpi=100)

(or shorter:)

fig, ax = plt.subplots(figsize=(8, 4), dpi=100)

It's a bit tricky:

  1. figsize actually controls the scale of the text relative to the plot extent (as well as the aspect ratio of the plot).

  2. dpi adjusts the size of the figure within the notebook (keeping constant the relative scale of the text and the plot aspect ratio).

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4

I wrote a modified version of the answer by @ryggyr that allows for more control over the individual parameters and works on multiple subplots:

def set_fontsizes(axes,size,title=np.nan,xlabel=np.nan,ylabel=np.nan,xticks=np.nan,yticks=np.nan):
    if type(axes) != 'numpy.ndarray':
        axes=np.array([axes])
    
    options = [title,xlabel,ylabel,xticks,yticks]
    for i in range(len(options)):
        if np.isnan(options[i]):
            options[i]=size
        
    title,xlabel,ylabel,xticks,yticks=options
    
    for ax in axes.flatten():
        ax.title.set_fontsize(title)
        ax.xaxis.label.set_size(xlabel)
        ax.yaxis.label.set_size(ylabel)
        ax.tick_params(axis='x', labelsize=xticks)
        ax.tick_params(axis='y', labelsize=yticks)
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1

Run:

plt.rcParams.keys()

to see all options for modifications, and change what you like in a similar manner:

plt.rcParams['font.size'] = 22

plt.rcParams['ytick.labelsize'] = 12

plt.rcParams["figure.figsize"] = (12, 12)
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