How to set font size of Matplotlib axis Legend?
Question:
I have a code like this:
import matplotlib.pyplot as plt
from matplotlib.pyplot import *
from matplotlib.font_manager import FontProperties
fontP = FontProperties()
fontP.set_size('xx-small')
fig=plt.figure()
ax1=fig.add_subplot(111)
plot([1,2,3], label="test1")
ax1.legend(loc=0, ncol=1, bbox_to_anchor=(0, 0, 1, 1),
prop = fontP,fancybox=True,shadow=False,title='LEGEND')
plt.show()
It can be seen in the plot that the setting in Fontsize does not affect the Legend Title font size.
How to set the font size of the legend title to a smaller size?
Answers:
I don’t know how to set it up for an individual plot, but I always do it globally:
plt.rc('legend',**{'fontsize':6})
I generally do in this way. Once the plot has been done i do the following
plt.legend(loc=0, numpoints=1)
leg = plt.gca().get_legend()
ltext = leg.get_texts()
plt.setp(ltext, fontsize='small')
I don’t know if this works for you
Here is how to change the fontsize of the legend list and/or legend title:
legend=plt.legend(list,loc=(1.05,0.05), title=r'$bf{Title}$') #Legend: list, location, Title (in bold)
legend.get_title().set_fontsize('6') #legend 'Title' fontsize
plt.setp(plt.gca().get_legend().get_texts(), fontsize='12') #legend 'list' fontsize
This is definitely an old question, but was frustrating me too and none of the other answers changed the legend title fontsize at all, but instead just changed the rest of the text. So after banging my head against the matplotlib documentation for awhile I came up with this.
legend = ax1.legend(loc=0, ncol=1, bbox_to_anchor=(0, 0, 1, 1),
prop = fontP,fancybox=True,shadow=False,title='LEGEND')
plt.setp(legend.get_title(),fontsize='xx-small')
As of Matplotlib 3.0.3, you can also set it globally with
plt.rcParams['legend.title_fontsize'] = 'xx-small'
This is the fastest:
plt.legend(loc=2,prop={'size':6})
Banged my head against it too, here is another more flowing way of doing it:
leg = ax.legend()
leg.set_title('A great legend',prop={'size':14})
Inspired by the current top answer, I found a slightly more natural way to change the fontsizes in the legend. The fontsize argument sets the font size of each of the data labels, and the title_fontsize argument sets the fontsize of the title, if you give the legend a title.
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.plot([0,1,2],[2,1,2],label='test_data (fs=12)')
ax.legend(fontsize=12, title='TITLE (fs=30)',title_fontsize=30)
Gives a figure like this:
Now in 2021, with matplotlib 3.4.2 you can set your legend fonts with
plt.legend(title="My Title", fontsize=10, title_fontsize=15)
where fontsize is the font size of the items in legend and title_fontsize is the font size of the legend title. More information in matplotlib documentation
The most easy method is using (it served me)
ax.legend(title = "anything", title_fontsize = 8, fontsize = 6)
title_fontsize is useful for changing the fontsize of the title
I’d like to point out that DougR‘s solution works even if your legend strings are raw strings used as Latex mathtext. And it is the only way I managed to change the font size of these mathtext strings .
I have a code like this:
import matplotlib.pyplot as plt
from matplotlib.pyplot import *
from matplotlib.font_manager import FontProperties
fontP = FontProperties()
fontP.set_size('xx-small')
fig=plt.figure()
ax1=fig.add_subplot(111)
plot([1,2,3], label="test1")
ax1.legend(loc=0, ncol=1, bbox_to_anchor=(0, 0, 1, 1),
prop = fontP,fancybox=True,shadow=False,title='LEGEND')
plt.show()
It can be seen in the plot that the setting in Fontsize does not affect the Legend Title font size.
How to set the font size of the legend title to a smaller size?
I don’t know how to set it up for an individual plot, but I always do it globally:
plt.rc('legend',**{'fontsize':6})
I generally do in this way. Once the plot has been done i do the following
plt.legend(loc=0, numpoints=1)
leg = plt.gca().get_legend()
ltext = leg.get_texts()
plt.setp(ltext, fontsize='small')
I don’t know if this works for you
Here is how to change the fontsize of the legend list and/or legend title:
legend=plt.legend(list,loc=(1.05,0.05), title=r'$bf{Title}$') #Legend: list, location, Title (in bold)
legend.get_title().set_fontsize('6') #legend 'Title' fontsize
plt.setp(plt.gca().get_legend().get_texts(), fontsize='12') #legend 'list' fontsize
This is definitely an old question, but was frustrating me too and none of the other answers changed the legend title fontsize at all, but instead just changed the rest of the text. So after banging my head against the matplotlib documentation for awhile I came up with this.
legend = ax1.legend(loc=0, ncol=1, bbox_to_anchor=(0, 0, 1, 1),
prop = fontP,fancybox=True,shadow=False,title='LEGEND')
plt.setp(legend.get_title(),fontsize='xx-small')
As of Matplotlib 3.0.3, you can also set it globally with
plt.rcParams['legend.title_fontsize'] = 'xx-small'
This is the fastest:
plt.legend(loc=2,prop={'size':6})
Banged my head against it too, here is another more flowing way of doing it:
leg = ax.legend()
leg.set_title('A great legend',prop={'size':14})
Inspired by the current top answer, I found a slightly more natural way to change the fontsizes in the legend. The fontsize argument sets the font size of each of the data labels, and the title_fontsize argument sets the fontsize of the title, if you give the legend a title.
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.plot([0,1,2],[2,1,2],label='test_data (fs=12)')
ax.legend(fontsize=12, title='TITLE (fs=30)',title_fontsize=30)
Gives a figure like this:
Now in 2021, with matplotlib 3.4.2 you can set your legend fonts with
plt.legend(title="My Title", fontsize=10, title_fontsize=15)
where fontsize is the font size of the items in legend and title_fontsize is the font size of the legend title. More information in matplotlib documentation
The most easy method is using (it served me)
ax.legend(title = "anything", title_fontsize = 8, fontsize = 6)
title_fontsize is useful for changing the fontsize of the title
I’d like to point out that DougR‘s solution works even if your legend strings are raw strings used as Latex mathtext. And it is the only way I managed to change the font size of these mathtext strings .