Image Merge & Resize
Combine, resize, or crop images — entirely in your browser
Drop images here or click to upload
Add up to 5 images (0/5 added)
Merge Settings
100% Private: Your images are processed entirely in your browser using the Canvas API. Nothing is uploaded to any server.
Three Tools in One
This tool combines three common image editing tasks into a single interface. The Merge / Stitch tab lets you combine up to five images into a single canvas — arranged side by side, stacked vertically, or in a two-column grid. You control the gap between images and the background color used to fill any space where images differ in size. The Resize tab lets you scale an image to exact pixel dimensions, with aspect-ratio locking to prevent distortion and social media presets for platforms like Instagram, YouTube, and Twitter. The Crop tab lets you drag a selection rectangle over a preview of your image; the selected region is extracted at full pixel resolution and saved as a new file.
How Browser-Based Processing Works
All three operations rely on the HTML5 Canvas API built into every modern browser. When you upload an image, it is read as a data URL using the FileReader API — the raw pixel data stays in your device's memory, never leaving it. For merging, the tool calculates the total canvas dimensions based on your chosen layout, then draws each image in the correct position using ctx.drawImage(). For resizing, a new canvas is created at the target dimensions and the source image is drawn scaled to fit. For cropping, the canvas is set to the selection size and only the selected region of the source image is drawn onto it. Each operation ends with canvas.toBlob(), which converts the final canvas to a downloadable file in PNG, JPEG, or WebP format.
When to Use Each Mode
- Merge horizontal — side-by-side comparison shots, before/after layouts, panoramic stitching of consecutive photos
- Merge vertical — stacking screenshots for documentation, recipe steps, tutorial slides
- Merge grid — photo collages, product grids, thumbnail previews
- Resize — optimizing images for web upload limits, matching platform dimension requirements, reducing file size before sending
- Crop — removing unwanted borders, isolating a subject, extracting a region from a screenshot
Output Format Guide
- PNG — lossless, supports transparency, best for screenshots, logos, and graphics with text
- JPEG — lossy compression, no transparency, smallest file sizes for photos and realistic imagery
- WebP — modern format that beats both PNG and JPEG for most use cases; supported in all current browsers