# How to put the legend outside the plot

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Problem :

I have a series of 20 plots (not subplots) to be made in a single figure. I want the legend to be outside of the box. At the same time, I do not want to change the axes, as the size of the figure gets reduced.

1. I want to keep the legend box outside the plot area. (I want the legend to be outside at the right side of the plot area).
2. Is there anyway that I reduce the font size of the text inside the legend box, so that the size of the legend box will be small.

Solution :

There are a number of ways to do what you want. To add to what @inalis and @Navi already said, you can use the `bbox_to_anchor` keyword argument to place the legend partially outside the axes and/or decrease the font size.

Before you consider decreasing the font size (which can make things awfully hard to read), try playing around with placing the legend in different places:

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

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
ax.plot(x, i * x, label='\$y = %ix\$' % i)

ax.legend()

plt.show()
``````

If we do the same thing, but use the `bbox_to_anchor` keyword argument we can shift the legend slightly outside the axes boundaries:

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

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
ax.plot(x, i * x, label='\$y = %ix\$' % i)

ax.legend(bbox_to_anchor=(1.1, 1.05))

plt.show()
``````

Similarly, make the legend more horizontal and/or put it at the top of the figure (I’m also turning on rounded corners and a simple drop shadow):

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

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
line, = ax.plot(x, i * x, label='\$y = %ix\$'%i)

ax.legend(loc='upper center', bbox_to_anchor=(0.5, 1.05),
plt.show()
``````

Alternatively, shrink the current plot’s width, and put the legend entirely outside the axis of the figure (note: if you use `tight_layout()`, then leave out `ax.set_position()`:

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

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
ax.plot(x, i * x, label='\$y = %ix\$'%i)

# Shrink current axis by 20%
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])

# Put a legend to the right of the current axis
ax.legend(loc='center left', bbox_to_anchor=(1, 0.5))

plt.show()
``````

And in a similar manner, shrink the plot vertically, and put a horizontal legend at the bottom:

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

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
line, = ax.plot(x, i * x, label='\$y = %ix\$'%i)

# Shrink current axis's height by 10% on the bottom
box = ax.get_position()
ax.set_position([box.x0, box.y0 + box.height * 0.1,
box.width, box.height * 0.9])

# Put a legend below current axis
ax.legend(loc='upper center', bbox_to_anchor=(0.5, -0.05),

plt.show()
``````

Have a look at the matplotlib legend guide. You might also take a look at `plt.figlegend()`.

## Placing the legend (`bbox_to_anchor`)

A legend is positioned inside the bounding box of the axes using the `loc` argument to `plt.legend`.
E.g. `loc="upper right"` places the legend in the upper right corner of the bounding box, which by default extents from `(0,0)` to `(1,1)` in axes coordinates (or in bounding box notation `(x0,y0, width, height)=(0,0,1,1)`).

To place the legend outside of the axes bounding box, one may specify a tuple `(x0,y0)` of axes coordinates of the lower left corner of the legend.

``````plt.legend(loc=(1.04,0))
``````

A more versatile approach is to manually specify the bounding box into which the legend should be placed, using the `bbox_to_anchor` argument. One can restrict oneself to supply only the `(x0, y0)` part of the bbox. This creates a zero span box, out of which the legend will expand in the direction given by the `loc` argument. E.g.

`plt.legend(bbox_to_anchor=(1.04,1), loc="upper left")`

places the legend outside the axes, such that the upper left corner of the legend is at position `(1.04,1)` in axes coordinates.

Further examples are given below, where additionally the interplay between different arguments like `mode` and `ncols` are shown.

``````l1 = plt.legend(bbox_to_anchor=(1.04,1), borderaxespad=0)
l2 = plt.legend(bbox_to_anchor=(1.04,0), loc="lower left", borderaxespad=0)
l3 = plt.legend(bbox_to_anchor=(1.04,0.5), loc="center left", borderaxespad=0)
l4 = plt.legend(bbox_to_anchor=(0,1.02,1,0.2), loc="lower left",
l5 = plt.legend(bbox_to_anchor=(1,0), loc="lower right",
bbox_transform=fig.transFigure, ncol=3)
l6 = plt.legend(bbox_to_anchor=(0.4,0.8), loc="upper right")
``````

Details about how to interpret the 4-tuple argument to `bbox_to_anchor`, as in `l4`, can be found in this question. The `mode="expand"` expands the legend horizontally inside the bounding box given by the 4-tuple. For a vertically expanded legend, see this question.

Sometimes it may be useful to specify the bounding box in figure coordinates instead of axes coordinates. This is shown in the example `l5` from above, where the `bbox_transform` argument is used to put the legend in the lower left corner of the figure.

### Postprocessing

Having placed the legend outside the axes often leads to the undesired situation that it is completely or partially outside the figure canvas.

Solutions to this problem are:

One can adjust the subplot parameters such, that the axes take less space inside the figure (and thereby leave more space to the legend) by using `plt.subplots_adjust`. E.g.

``````plt.subplots_adjust(right=0.7)
``````

leaves 30% space on the right-hand side of the figure, where one could place the legend.

• Tight layout
Using `plt.tight_layout` Allows to automatically adjust the subplot parameters such that the elements in the figure sit tight against the figure edges. Unfortunately, the legend is not taken into account in this automatism, but we can supply a rectangle box that the whole subplots area (including labels) will fit into.

``````plt.tight_layout(rect=[0,0,0.75,1])
``````
• Saving the figure with `bbox_inches = "tight"`
The argument `bbox_inches = "tight"` to `plt.savefig` can be used to save the figure such that all artist on the canvas (including the legend) are fit into the saved area. If needed, the figure size is automatically adjusted.

``````plt.savefig("output.png", bbox_inches="tight")
``````
• automatically adjusting the subplot params
A way to automatically adjust the subplot position such that the legend fits inside the canvas without changing the figure size can be found in this answer: Creating figure with exact size and no padding (and legend outside the axes)

Comparison between the cases discussed above:

## Alternatives

A figure legend

One may use a legend to the figure instead of the axes, `matplotlib.figure.Figure.legend`. This has become especially useful for matplotlib version >=2.1, where no special arguments are needed

``````fig.legend(loc=7)
``````

to create a legend for all artists in the different axes of the figure. The legend is placed using the `loc` argument, similar to how it is placed inside an axes, but in reference to the whole figure – hence it will be outside the axes somewhat automatically. What remains is to adjust the subplots such that there is no overlap between the legend and the axes. Here the point “Adjust the subplot parameters” from above will be helpful. An example:

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

x = np.linspace(0,2*np.pi)
colors=["#7aa0c4","#ca82e1" ,"#8bcd50","#e18882"]
fig, axes = plt.subplots(ncols=2)
for i in range(4):
axes[i//2].plot(x,np.sin(x+i), color=colors[i],label="y=sin(x+{})".format(i))

fig.legend(loc=7)
fig.tight_layout()
plt.show()
``````

Legend inside dedicated subplot axes

An alternative to using `bbox_to_anchor` would be to place the legend in its dedicated subplot axes (`lax`).
Since the legend subplot should be smaller than the plot, we may use `gridspec_kw={"width_ratios":[4,1]}` at axes creation.
We can hide the axes `lax.axis("off")` but still put a legend in. The legend handles and labels need to obtained from the real plot via `h,l = ax.get_legend_handles_labels()`, and can then be supplied to the legend in the `lax` subplot, `lax.legend(h,l)`. A complete example is below.

``````import matplotlib.pyplot as plt
plt.rcParams["figure.figsize"] = 6,2

fig, (ax,lax) = plt.subplots(ncols=2, gridspec_kw={"width_ratios":[4,1]})
ax.plot(x,y, label="y=sin(x)")
....

h,l = ax.get_legend_handles_labels()
lax.axis("off")

plt.tight_layout()
plt.show()
``````

This produces a plot, which is visually pretty similar to the plot from above:

We could also use the first axes to place the legend, but use the `bbox_transform` of the legend axes,

``````ax.legend(bbox_to_anchor=(0,0,1,1), bbox_transform=lax.transAxes)
lax.axis("off")
``````

In this approach, we do not need to obtain the legend handles externally, but we need to specify the `bbox_to_anchor` argument.

• Consider the matplotlib legend guide with some examples of other stuff you want to do with legends.
• Some example code for placing legends for pie charts may directly be found in answer to this question: Python – Legend overlaps with the pie chart
• The `loc` argument can take numbers instead of strings, which make calls shorter, however, they are not very intuitively mapped to each other. Here is the mapping for reference:

Just call `legend()` call after the `plot()` call like this:

``````# matplotlib
plt.plot(...)
plt.legend(loc='center left', bbox_to_anchor=(1, 0.5))

# Pandas
df.myCol.plot().legend(loc='center left', bbox_to_anchor=(1, 0.5))
``````

Results would look something like this:

``````import matplotlib.pyplot as plt
from matplotlib.font_manager import FontProperties

fontP = FontProperties()
fontP.set_size('xx-small')

p1, = plt.plot([1, 2, 3], label='Line 1')
p2, = plt.plot([3, 2, 1], label='Line 2')
plt.legend(handles=[p1, p2], title='title', bbox_to_anchor=(1.05, 1), loc='upper left', prop=fontP)
``````

• As noted by Mateen Ulhaq, `fontsize='xx-small'` also works, without importing `FontProperties`.
``````plt.legend(handles=[p1, p2], title='title', bbox_to_anchor=(1.05, 1), loc='upper left', fontsize='xx-small')
``````

To place the legend outside the plot area, use `loc` and `bbox_to_anchor` keywords of `legend()`. For example, the following code will place the legend to the right of the plot area:

``````legend(loc="upper left", bbox_to_anchor=(1,1))
``````

Short answer: you can use `bbox_to_anchor` + `bbox_extra_artists` + `bbox_inches='tight'`.

You can use `bbox_to_anchor` to manually specify the location of the legend box, as some other people have pointed out in the answers.

However, the usual issue is that the legend box is cropped, e.g.:

``````import matplotlib.pyplot as plt

# data
all_x = [10,20,30]
all_y = [[1,3], [1.5,2.9],[3,2]]

# Plot
fig = plt.figure(1)
ax.plot(all_x, all_y)

# Add legend, title and axis labels
lgd = ax.legend( [ 'Lag ' + str(lag) for lag in all_x], loc='center right', bbox_to_anchor=(1.3, 0.5))
ax.set_title('Title')
ax.set_xlabel('x label')
ax.set_ylabel('y label')

fig.savefig('image_output.png', dpi=300, format='png')
``````

In order to prevent the legend box from getting cropped, when you save the figure you can use the parameters `bbox_extra_artists` and `bbox_inches` to ask `savefig` to include cropped elements in the saved image:

`fig.savefig('image_output.png', bbox_extra_artists=(lgd,), bbox_inches='tight')`

Example (I only changed the last line to add 2 parameters to `fig.savefig()`):

``````import matplotlib.pyplot as plt

# data
all_x = [10,20,30]
all_y = [[1,3], [1.5,2.9],[3,2]]

# Plot
fig = plt.figure(1)
ax.plot(all_x, all_y)

# Add legend, title and axis labels
lgd = ax.legend( [ 'Lag ' + str(lag) for lag in all_x], loc='center right', bbox_to_anchor=(1.3, 0.5))
ax.set_title('Title')
ax.set_xlabel('x label')
ax.set_ylabel('y label')

fig.savefig('image_output.png', dpi=300, format='png', bbox_extra_artists=(lgd,), bbox_inches='tight')
``````

I wish that matplotlib would natively allow outside location for the legend box as Matlab does:

``````figure
x = 0:.2:12;
plot(x,besselj(1,x),x,besselj(2,x),x,besselj(3,x));
hleg = legend('First','Second','Third',...
'Location','NorthEastOutside')
% Make the text of the legend italic and color it brown
set(hleg,'FontAngle','italic','TextColor',[.3,.2,.1])
``````

In addition to all the excellent answers here, newer versions of `matplotlib` and `pylab` can automatically determine where to put the legend without interfering with the plots, if possible.

``````pylab.legend(loc='best')
``````

This will automatically place the legend away from the data if possible!

However, if there is no place to put the legend without overlapping the data, then you’ll want to try one of the other answers; using `loc="best"` will never put the legend outside of the plot.

Short Answer: Invoke draggable on the legend and interactively move it wherever you want:

``````ax.legend().draggable()
``````

Long Answer: If you rather prefer to place the legend interactively/manually rather than programmatically, you can toggle the draggable mode of the legend so that you can drag it to wherever you want. Check the example below:

``````import matplotlib.pylab as plt
import numpy as np
#define the figure and get an axes instance
fig = plt.figure()
#plot the data
x = np.arange(-5, 6)
ax.plot(x, x*x, label='y = x^2')
ax.plot(x, x*x*x, label='y = x^3')
ax.legend().draggable()
plt.show()
``````

Not exactly what you asked for, but I found it’s an alternative for the same problem.
Make the legend semi-transparant, like so:

Do this with:

``````fig = pylab.figure()
ax.plot(x,y,label=label,color=color)
# Make the legend transparent:
ax.legend(loc=2,fontsize=10,fancybox=True).get_frame().set_alpha(0.5)
# Make a transparent text box
ax.text(0.02,0.02,yourstring, verticalalignment='bottom',
horizontalalignment='left',
fontsize=10,
transform=self.ax.transAxes)
``````

It’s worth refreshing this question, as newer versions of Matplotlib have made it much easier to position the legend outside the plot. I produced this example with Matplotlib version `3.1.1`.

Users can pass a 2-tuple of coordinates to the `loc` parameter to position the legend anywhere in the bounding box. The only gotcha is you need to run `plt.tight_layout()` to get matplotlib to recompute the plot dimensions so the legend is visible:

``````import matplotlib.pyplot as plt

plt.plot([0, 1], [0, 1], label="Label 1")
plt.plot([0, 1], [0, 2], label='Label 2')

plt.legend(loc=(1.05, 0.5))
plt.tight_layout()
``````

This leads to the following plot:

References:

``````import plotly
import math
import random
import numpy as np
``````

I simply used the string `'center left'` for the location, like in matlab.
I imported pylab from matplotlib.

see the code as follow:

``````from matplotlib as plt
from matplotlib.font_manager import FontProperties
t = A[:,0]
sensors = A[:,index_lst]

for i in range(sensors.shape[1]):
plt.plot(t,sensors[:,i])

plt.xlabel('s')
plt.ylabel('°C')
lgd = plt.legend(loc='center left', bbox_to_anchor=(1, 0.5),fancybox = True, shadow = True)
``````

Something along these lines worked for me. Starting with a bit of code taken from Joe, this method modifies the window width to automatically fit a legend to the right of the figure.

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

plt.ion()

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
ax.plot(x, i * x, label='\$y = %ix\$'%i)

# Put a legend to the right of the current axis
leg = ax.legend(loc='center left', bbox_to_anchor=(1, 0.5))

plt.draw()

# Get the ax dimensions.
box = ax.get_position()
xlocs = (box.x0,box.x1)
ylocs = (box.y0,box.y1)

# Get the figure size in inches and the dpi.
w, h = fig.get_size_inches()
dpi = fig.get_dpi()

# Get the legend size, calculate new window width and change the figure size.
legWidth = leg.get_window_extent().width
winWidthNew = w*dpi+legWidth
fig.set_size_inches(winWidthNew/dpi,h)

# Adjust the window size to fit the figure.
mgr = plt.get_current_fig_manager()
mgr.window.wm_geometry("%ix%i"%(winWidthNew,mgr.window.winfo_height()))

# Rescale the ax to keep its original size.
factor = w*dpi/winWidthNew
x0 = xlocs[0]*factor
x1 = xlocs[1]*factor
width = box.width*factor
ax.set_position([x0,ylocs[0],x1-x0,ylocs[1]-ylocs[0]])

plt.draw()
``````

You can also try `figlegend`. It is possible to create a legend independent of any Axes object. However, you may need to create some “dummy” Paths to make sure the formatting for the objects gets passed on correctly.

The solution that worked for me when I had huge legend was to use extra empty image layout.
In following example I made 4 rows and at the bottom I plot image with offset for legend (bbox_to_anchor) at the top it does not get cut.

``````f = plt.figure()
lgd = ax.legend(loc='upper left', bbox_to_anchor=(0, 4), mode="expand", borderaxespad=0.3)
ax.autoscale_view()
plt.savefig(fig_name, format='svg', dpi=1200, bbox_extra_artists=(lgd,), bbox_inches='tight')
``````

Here’s another solution, similar to adding `bbox_extra_artists` and `bbox_inches`, where you don’t have to have your extra artists in the scope of your `savefig` call. I came up with this since I generate most of my plot inside functions.

Instead of adding all your additions to the bounding box when you want to write it out, you can add them ahead of time to the `Figure`‘s artists. Using something similar to Franck Dernoncourt’s answer above:

``````import matplotlib.pyplot as plt

# data
all_x = [10,20,30]
all_y = [[1,3], [1.5,2.9],[3,2]]

# plotting function
def gen_plot(x, y):
fig = plt.figure(1)
ax.plot(all_x, all_y)
lgd = ax.legend( [ "Lag " + str(lag) for lag in all_x], loc="center right", bbox_to_anchor=(1.3, 0.5))
fig.artists.append(lgd) # Here's the change
ax.set_title("Title")
ax.set_xlabel("x label")
ax.set_ylabel("y label")
return fig

# plotting
fig = gen_plot(all_x, all_y)

# No need for `bbox_extra_artists`
fig.savefig("image_output.png", dpi=300, format="png", bbox_inches="tight")
``````

Here’s the generated plot.

Here is an example from the matplotlib tutorial found here. This is one of the more simpler examples but I added transparency to the legend and added plt.show() so you can paste this into the interactive shell and get a result:

``````import matplotlib.pyplot as plt
p1, = plt.plot([1, 2, 3])
p2, = plt.plot([3, 2, 1])
p3, = plt.plot([2, 3, 1])
plt.legend([p2, p1, p3], ["line 1", "line 2", "line 3"]).get_frame().set_alpha(0.5)
plt.show()
``````