How to increase plt.title font size?

Question

fontsize can be assigned inside dictionary fontdict which provides additional parameters fontweight, verticalalignment , horizontalalignment

The below snippet should work

plt.title('Temperature \n Humidity', fontdict = {'fontsize' : 100})

import matplotlib.pyplot as plt
plt.figtext(.5,.9,'Temperature', fontsize=100, ha='center')
plt.figtext(.5,.8,'Humidity',fontsize=30,ha='center')
plt.show()

Probably you want this. You can easily tweak the fontsize of both and adjust there placing by changing the first two figtext positional parameters. ha is for horizontal alignment

Alternatively,

import matplotlib.pyplot as plt

fig = plt.figure() # Creates a new figure
fig.suptitle('Temperature', fontsize=50) # Add the text/suptitle to figure

ax = fig.add_subplot(111) # add a subplot to the new figure, 111 means "1x1 grid, first subplot"
fig.subplots_adjust(top=0.80) # adjust the placing of subplot, adjust top, bottom, left and right spacing  
ax.set_title('Humidity',fontsize= 30) # title of plot

ax.set_xlabel('xlabel',fontsize = 20) #xlabel
ax.set_ylabel('ylabel', fontsize = 20)#ylabel

x = [0,1,2,5,6,7,4,4,7,8]
y = [2,4,6,4,6,7,5,4,5,7]

ax.plot(x,y,'-o') #plotting the data with marker '-o'
ax.axis([0, 10, 0, 10]) #specifying plot axes lengths
plt.show()

Output of alternative code:

PS: if this code give error like ImportError: libtk8.6.so: cannot open shared object file esp. in Arch like systems. In that case, install tk using sudo pacman -S tk or Follow this link

This has been mostly working for me across recent versions of Matplotlib (currently 2.0.2). It is helpful for generating presentation graphics:

def plt_resize_text(labelsize, titlesize):
    ax = plt.subplot()
    for ticklabel in (ax.get_xticklabels()):
        ticklabel.set_fontsize(labelsize)
    for ticklabel in (ax.get_yticklabels()):
        ticklabel.set_fontsize(labelsize)
    ax.xaxis.get_label().set_fontsize(labelsize)
    ax.yaxis.get_label().set_fontsize(labelsize)
    ax.title.set_fontsize(titlesize)

The odd for-loop construction seems to be necessary to adjust the size of each tic label. Also, the above function should be called just before the call to plt.show(block=True), otherwise for whatever reason the title size occasionally remains unchanged.

Assuming you are using matplotlib to render some plots.

You might want to checkout Text rendering With LaTeX — Matplotlib

Here are some lines of code for your case

plt.rc('text', usetex=True)
plt.title(r"\begin{center} {\Large Temperature} \par {\large Humidity} \end{center}")

Hope that helps.

Simply do the following: ax.set_title('This is the title',fontsize=20)