Pair plot

seaborn.pairplot() creates a grid of scatterplots and histograms (or KDEs) for pairwise relationships between numeric variables in a dataset.

It’s one of Seaborn’s most powerful exploratory tools, showing how each variable:

• correlates with others (scatterplots), and
• distributes individually (histograms or density plots on the diagonal).

Syntax:

Parameters:

• data = DataFrame with numeric columns
• hue = Variable to colour-code data points by category
• vars = List of variables to include (both x and y)
• x_vars, y_vars = Lists of variables for x and y axes (for asymmetric grids)
• kind = Plot type: "scatter" (default) or "kde"
• diag_kind = Plot type on the diagonal: "auto", "hist", or "kde"
• markers = Marker style for scatterplots
• palette = Colour palette for hue categories
• corner = If True, show only the lower triangle of plots
• plot_kws, diag_kws, grid_kws = Keyword arguments for customising subplots
• height = Height (in inches) of each subplot
• aspect = Aspect ratio of each subplot
• dropna = Whether to drop missing values
• context = Set a plotting context (e.g., "talk", "notebook")

Basic example

Creates a scatterplot matrix for all numeric columns in iris. Diagonal = histograms of each variable. Off-diagonal = pairwise scatterplots.

Add hue (colour by category)

Colours each species differently. Great for class separation or cluster analysis.

Use KDE instead of scatterplots

Shows smooth density contours instead of discrete points. Great for large datasets or overlapping points.

Change diagonal plot type

Replaces histograms on the diagonal with KDE (smoothed density) curves.

Select specific variables

Only plots relationships among selected columns. Useful for focusing on variables of interest.

Asymmetric grids (x_vars vs y_vars)

Creates a non-square grid — useful for comparing two sets of variables.

Show only lower triangle (corner)

Hides the upper triangle, reducing redundancy. Common in publications for clarity.

Change marker style

Uses different marker shapes for each category in hue.

Pass custom plotting options

Adds transparency, size, and edges to scatter points. Smooths and thickens KDEs/histograms on the diagonal.

Pairplot with regression lines

Adds linear regression lines in each scatterplot. Equivalent to calling sns.lmplot() for every pair.