Compare Two Images Side by Side
Put two pictures next to each other, zoom in sync, and spot every difference — free, no installation.
100% free · No sign-up · Runs in your browser
Start comparing 2 images →Comparing two images with your operating system's default viewer means juggling two windows and never being sure both are at the same zoom level. This tool opens both pictures in one window, side by side, with synchronized zoom and pan — when you zoom into a detail on the left, the right image follows to the exact same spot.
Beyond the basic side-by-side view, you can switch to a curtain slider to swipe between the two images, run a pixel diff that highlights changed areas in red, or use A/B flash to flip between them in place — the fastest way for your eyes to catch subtle differences.
How to use
- 1Open the tool — it starts with two empty zones by default.
- 2Drop an image into each zone, paste from clipboard (Ctrl+V), or load from a URL.
- 3Turn on "Sync zoom & pan" and inspect details, or switch to Pixel Diff / Curtain / A/B Flash mode.
Why use this tool
Synchronized zoom & pan
Zoom into the same region of both images at once — essential for checking sharpness, compression artifacts or retouching.
Four comparison modes
Side-by-side grid, curtain slider, pixel diff with adjustable threshold, and A/B flash toggle.
Private by design
Images are processed entirely in your browser. Nothing is uploaded to a server.
Frequently Asked Questions
Can I compare images of different sizes?
Yes. Each zone scales its image independently, and you can zoom and pan each one freely. Pixel diff works best when both images share the same dimensions.
Do I need to create an account?
No. The tool is completely free with no registration, no watermark and no usage limit.
Are my images uploaded anywhere?
No. All processing happens locally in your browser — your images never leave your computer.