Image Merger

Combine multiple images into a single image 100% client-side. Adjust custom layouts, gaps, backgrounds, aspect ratios, and export outputs securely in your browser.

100% Secure & Client-Side Image Merger — Combine Photos Instantly

Need to join two screenshots side-by-side, build a vertical photo sequence, or compose an absolute custom collage? ToolZeno's Image Merger provides a secure, developer-grade utility to merge multiple images into a single high-resolution file. By executing entirely client-side using your browser's native Canvas APIs and background Web Workers, your images never leave your local computer. This guarantees instant processing, zero bandwidth consumption, and total compliance with privacy-first standards.

Vertical Stack, Horizontal Row, Grid & Custom Layouts

Selecting the correct layout organizes your merged asset for different publication channels:

Layout PresetGrid Spacing FeaturesAlignment RulesBest Used For
Vertical StackGaps, Outer paddingLeft, Center, RightInfographics, vertical screenshots, social feeds, story sequences
Horizontal RowGaps, Outer paddingTop, Middle, BottomBefore-and-after comparisons, banner creations, panoramas
Grid ModeCols count, Gaps, PaddingDual alignmentsPhoto sheets, image grids, catalog thumbnails, batch summaries
Custom CanvasCoordinate parametersManual drag/resizeFigma-like mockups, custom collages, overlapping structures, watermark overlays

Advanced Layout Fine-Tuning

Unlike basic tools that stretch or crop photos blindly, ToolZeno gives you full control over resizing behaviors and spacing gaps. Choose to maintain original dimensions, fit everything proportionally within grid slots, cover cells completely (center-cropped), or stretch values (with non-proportional aspect warnings). Additionally, customize transparent spacing borders, solid backdrops, or radial/linear gradients to elevate visual presentation.

Why Choose Local Browser Processing?

  • Ironclad Privacy: Your photos are processed completely offline inside your browser sandbox. They are never uploaded to our servers, keeping sensitive screenshots secure.
  • Hardware-Accelerated Speeds: We utilize native Web Workers and canvas APIs to handle encoding calculations, rendering giant multi-megabyte images in milliseconds without network delays.
  • Interactive Custom Collages: Our custom canvas layout lets you select, drag, and scale images interactively directly inside the preview pane.
  • Flexible Sizing & Gradients: Adjust canvas padding, spacing, background linear/radial colors, and export outputs (PNG, JPG, WebP, AVIF) at custom qualities.

Frequently Asked Questions

Client-side image merging uses standard HTML5 Canvas APIs, OffscreenCanvas, and Web Workers. When you upload multiple images, they are decoded directly in your browser's local RAM. Our layout engine calculates rendering coordinates, and the canvas draws them alongside background presets (solid or gradient colors). Finally, the canvas encodes the pixels into the selected format (PNG, JPG, WebP, or AVIF) for local download. Your files never touch any remote server.

We support four layouts: (1) Vertical Stack, which aligns images in a vertical column; (2) Horizontal Row, which aligns images side-by-side; (3) Grid, which distributes images evenly into custom rows and columns; and (4) Custom Canvas, which lets you click, drag, and resize individual image layers freely like a design editor.

There is no hardcoded limitation on the number of uploads. However, since the merging process runs 100% in your device's memory (RAM), uploading extremely large files (e.g. greater than 50MB each) or processing dozens of photos simultaneously may exceed mobile browser heap limitations. For large grids, we recommend utilizing a desktop browser.

PNG is lossless and supports transparency, making it the ideal choice for text screenshots, logos, and illustrations to prevent color bleed or blur. JPG is lossy and doesn't support transparency, but produces much smaller file sizes for photographs. WebP and AVIF offer modern, next-generation compression that achieves high fidelity at extremely low weights, which is optimal for web performance.

Yes. In our layers panel, you can drag and drop images to rearrange their stacking order. Keyboard users can focus on any item in the layer list and press ArrowUp or ArrowDown to swap position layout indices dynamically.