How to set the range of Y-axis in Python Plotly?

Plotly is a powerful Python library for creating interactive visualizations. One common requirement is controlling the Y-axis range to better display your data or focus on specific value ranges.

Setting Y-axis Range with update_layout()

The most straightforward way to set the Y-axis range is using the update_layout() method with the yaxis_range parameter ?

import plotly.graph_objs as go
import numpy as np

# Set random seed for reproducible results
np.random.seed(3)

# Generate X-axis data (0 to 18, step 2)
x_values = list(range(0, 20, 2))

# Generate random Y-axis data
y_values = np.random.randn(10)

# Create scatter plot with line mode
fig = go.Figure(data=go.Scatter(x=x_values, y=y_values, mode='lines'))

# Set Y-axis range from -3 to 3
fig.update_layout(yaxis_range=[-3, 3])

# Display the plot
fig.show()

Alternative Method Using yaxis Dictionary

You can also set the Y-axis range using the yaxis dictionary approach ?

import plotly.graph_objs as go
import numpy as np

np.random.seed(3)
x_values = list(range(0, 20, 2))
y_values = np.random.randn(10)

# Create figure and set Y-axis range using yaxis dictionary
fig = go.Figure(data=go.Scatter(x=x_values, y=y_values, mode='lines'))
fig.update_layout(
    yaxis=dict(range=[-2, 2])
)

fig.show()

Setting Range During Figure Creation

You can also specify the Y-axis range when creating the figure layout ?

import plotly.graph_objs as go
import numpy as np

np.random.seed(3)
x_values = list(range(0, 20, 2))
y_values = np.random.randn(10)

# Create figure with Y-axis range specified in layout
fig = go.Figure(
    data=go.Scatter(x=x_values, y=y_values, mode='lines'),
    layout=go.Layout(yaxis=dict(range=[-1, 1]))
)

fig.show()

Key Parameters

Conclusion

Use update_layout(yaxis_range=[min, max]) to set Y-axis range in Plotly. This method gives you precise control over the visible data range and improves chart readability for your specific use case.