How to Combine Two Images Side by Side

You want two photos side by side. A before-and-after comparison. A two-shot of you and a friend. A diptych for posting. Comparison photos for a product review. Two screenshots that go together.

The operation is simple in concept but most software handles it awkwardly. Here are the practical paths.

The fastest way: phone screenshot trick

For iPhone or Android, the fastest hack:

Open both photos in your gallery, one in each “split screen” or “multitasking” view
Screenshot the whole screen
Crop to just the combined view

Crude but instant. Quality is limited to your screen size, but for casual sharing it’s enough.

For better quality, use one of the dedicated approaches below.

Phone apps (best quality)

iPhone:

Shortcuts app (built-in): create a “Combine Images” shortcut once, reuse forever. Add the “Combine Images” action, configure for horizontal layout.
Pic Stitch (free, App Store): templates for side-by-side and various other layouts
Layout from Instagram (free): designed for combining 2-4 photos into one
Photos app (recent iOS): some iOS versions let you combine via the share sheet

Android:

Google Photos: select two photos → tap ”+” → “Collage” → choose side-by-side layout
Pic Stitch (free, Play Store): same as iOS
Layout from Instagram (free)
Manufacturer’s gallery app (Samsung Gallery, etc.) often has built-in collage

Browser-based: simple workflow with our tools

We don’t have a dedicated “combine images” tool, but the workflow with existing tools is straightforward:

Approach 1: bundle into a PDF, then convert pages back to images

For a quick side-by-side that doesn’t need pixel-perfect alignment:

Use JPG to PDF with 2-up layout (two images per page) — your PDF has both photos on one page side-by-side
Use PDF to Images to convert that one PDF page back to a single image

The result is a single image with both photos side-by-side. Quality depends on the PDF rendering DPI you pick.

This is round-about. For repeated use, the phone or desktop approaches are better.

Approach 2: stack images vertically with HTML+screenshot

A nerdy but fast approach if you have a moment of patience:

Create a simple HTML file:

<html><body><div style="display:flex">
<img src="a.jpg" style="height:600px">
<img src="b.jpg" style="height:600px">
</div></body></html>

Open in a browser, screenshot the page
Crop the screenshot

Total time: about a minute. Free, runs locally, no software install.

Desktop: free tools that do it right

Photopea (free, browser-based, Photoshop-like): photopea.com

Open Photopea
File → New → set canvas size to (combined width × max height)
Drag both images in as layers
Position side by side
File → Export As → PNG or JPG

GIMP (free, desktop):

Similar workflow with layers
More features but more learning curve

Preview on Mac:

Open both images in Preview
Edit → Insert → From File (or drag the second image into the first’s window in a way that creates a combined canvas)
Save the combined image

The Preview approach has some quirks; varies by macOS version.

Microsoft Paint or Paint 3D (Windows):

Open one image, resize the canvas larger
Paste the second image, position
Save

Basic but functional.

Aligning the images

Common alignment options:

Equal heights: both photos sized to the same vertical dimension. The combined image is width1 + width2 × max_height. Most common look for “two photos side-by-side.”

Equal widths: both photos sized to the same horizontal dimension, stacked vertically. Less common for side-by-side; more for top/bottom.

Fixed total dimensions: target a final size (e.g., 1080×1080 for Instagram), fit both photos within it. May require cropping each.

Resize both to match first: scale the second photo to match the first’s height (or width). Photos rendered next to each other look “balanced.”

For most uses, “equal heights” is the right default. Photos at the same height visually flow well even if the widths differ.

Adding a gap, border, or text

Most “combined images” benefit from a small gap between the photos:

Solid white or black border between the two photos (10-20 pixels) separates them visually
Text labels (“Before” / “After”, etc.) clarify what each image is
Shadow or outline around each image gives a polished feel

Tools that handle gaps and labels well: phone collage apps (Pic Stitch, Layout), Canva (free with account, web-based), Photopea (free, browser).

Common use cases

Before/after photos: weight loss progress, room redecoration, repair work. Side-by-side immediately communicates change.

Product comparison: two products to compare, photographed against the same background.

Travel photos: two related shots from the same location (interior + exterior, different angles).

Social media posts: many platforms (Instagram especially) reward longer dwell time on richer content; a two-photo combined image is more compelling than a single.

Forum / community contributions: showing both sides of a problem (a question and the answer, a problem and the solution).

Memes and comparisons: humor often relies on side-by-side juxtaposition.

Tips for visual quality

Match the lighting: photos with very different lighting (one bright, one shadowed) look jarring side-by-side. Either re-photograph or adjust brightness in each.

Match the aspect ratios: a tall portrait next to a wide landscape looks unbalanced. Crop or rearrange to balance.

Match the color tones: if one photo is warm-tone and the other cool, they fight visually. Use color correction on one to match the other (rough method: just bump contrast or warmth in any photo editor).

Crop tight: dead space in either photo dilutes impact. Use Image Cropper to remove backgrounds.

Consistent quality: don’t combine a high-resolution photo with a low-resolution one. The pixelated photo will draw the eye to its lower quality.

After combining

Compress for sharing: Image Compressor at quality 0.85 typically shrinks combined images by 50-70% with no visible loss.

Resize for social media: each platform has different ideal dimensions. See our Image Cropping for Social Media guide.

Strip metadata: EXIF Stripper before sharing publicly removes location and other embedded info.

TL;DR

Quickest path: phone apps (Layout from Instagram, Pic Stitch, Google Photos collage)
Best quality: free desktop tools (Photopea browser, GIMP, Preview on Mac)
No app needed: HTML+screenshot for technical users
Workaround with our tools: JPG to PDF 2-up + PDF to Images
Match heights, lighting, and crop tight for the best visual balance
After: compress and resize for the target use