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Image Guide

How to merge two images together online

Add two photos, choose a side-by-side or vertical layout, adjust their order and spacing, then download one PNG, JPG, or WebP image.

Online image merger showing two photos arranged side by side and ready to export as one image.
Two images combined side by sideThe basic workflow is add two images, choose the reading direction, preview the shared canvas, and export one file.

Direct answer

To merge two images together, add both files to an image merger, choose Horizontal for a side-by-side result or Vertical for a top-to-bottom result, reorder the files, adjust size matching and spacing, then export the combined canvas as PNG, JPG, or WebP.

What happens when two images are merged

Local input

File selection and drag-and-drop

The browser File API can expose files that a user selects or drops into a page, allowing a local preview and processing workflow without treating upload as a required first step.

Source: MDN: Using files from web applications

Composition

Canvas drawImage()

Each source can be drawn at a chosen x and y position and scaled to a target width and height. That is the basis for side-by-side, vertical, grid, and freestyle layouts.

Source: MDN: Canvas drawImage()

Export

PNG, JPEG, or WebP blob

Canvas toBlob() creates an image blob from the final canvas. PNG support is required, while many browsers also support JPEG and WebP export.

Source: MDN: Canvas toBlob()

Format choice

PNG for transparency; JPEG or WebP for photos

PNG preserves transparency and sharp graphical detail. JPEG and WebP can reduce photographic file size, but lossy quality settings should be checked around text and fine edges.

Source: MDN: Image file type and format guide

Practical use cases

The right layout depends on what the finished image needs to communicate. Comparisons usually work side by side, sequential screenshots read better vertically, and mixed photo sets need a grid or a freely arranged canvas.

Before-and-after comparison

Horizontal2 images

Renovations, product results, design revisions, progress photos, and any pair that should be compared at a glance.

Place the earlier image first, match heights, use a small gap or divider, and export at a width that remains readable on the target platform.

Long screenshot or conversation

Vertical2+ images

Web pages, app screens, receipts, instructions, and conversations that continue from top to bottom.

Order screenshots chronologically, match widths, set spacing to zero for a continuous stitch, and inspect the seam before export.

Balanced photo pair or grid

Grid2-20 images

Listings, event recaps, moodboards, product variants, and photo collections that need equal visual weight.

Choose the number of columns, keep spacing consistent, and use a background color that suits every photo.

Custom collage

Freestyle2-20 images

Overlapping photos, scrapbook layouts, thumbnail compositions, and arrangements with intentional size differences.

Set the canvas size first, then move, resize, and layer each image while keeping important content away from the edges.

How to merge two images step by step

Four steps for merging two images: add files, choose a layout, adjust spacing and size, then export.
Four-step image merging workflowCheck image order, edge alignment, spacing, background, and output format before downloading.
  1. 1

    Add both source images

    Choose, drop, or paste two JPG, PNG, WebP, GIF, AVIF, or BMP files. Start with the highest-resolution originals available so the final export has enough detail.

  2. 2

    Choose horizontal or vertical

    Use Horizontal to put the images side by side. Use Vertical to place one above the other. Drag to reorder them so the comparison or sequence reads correctly.

  3. 3

    Match dimensions and tune spacing

    Match image sizes when a clean shared edge matters. Then set alignment, spacing, outside margin, corner radius, and a transparent or solid background.

  4. 4

    Preview and export one image

    Inspect the full canvas for stretched content, awkward gaps, and unreadable text. Choose PNG for transparency or sharp graphics, or JPG/WebP with a suitable quality level for photographs.

Choose the right way to combine your images

Start with the reading direction of the final image. Horizontal layouts emphasize comparison, vertical layouts preserve a sequence, grids create equal visual weight, and freestyle canvases are for overlap or custom positioning.

Comparison of side-by-side, vertical stack, photo grid, and freestyle canvas image merge layouts.
Horizontal, vertical, grid, and freestyle layoutsChoose the layout from the job: compare, stitch, balance, or position freely.
GoalBest layoutKey setting
Compare two photos at a glanceHorizontalMatch heights and use a small gap or divider.
Continue one screenshot below anotherVerticalMatch widths, preserve order, and set spacing to zero.
Give several images equal visual weightGridChoose the column count and keep spacing consistent.
Overlap, resize, or position images independentlyFreestyleSet the canvas dimensions before arranging each image.

Merge two images with iTextMaster Image Merger

iTextMaster Image Merger combines up to 20 images locally in the browser. For a two-image job, choose Horizontal or Vertical, drag the files into the right order, match their dimensions when needed, and export the full-resolution result without a watermark.

Related image tools

FAQ

How do I merge two images together online?

Add both images to an online image merger, choose Horizontal or Vertical, arrange their order, adjust spacing and size matching, then download the combined image.

How do I put two pictures side by side?

Choose a Horizontal layout. Match the image heights for a straight top and bottom edge, then add a gap, margin, or background if the pair needs separation.

Can I join two screenshots vertically?

Yes. Choose a Vertical layout, put the first screenshot on top, match widths, and set spacing to zero if you want a continuous long image.

Will merging two images reduce quality?

The layout itself does not require quality loss, but scaling and lossy JPG or WebP export can change detail. Use suitable source dimensions and inspect the full-resolution download.

Which format should I use for the merged image?

Use PNG for transparency, screenshots, text, or sharp graphics. Use JPG or WebP for photographs when a smaller file matters, and adjust quality carefully.

Can I merge images with different sizes?

Yes. You can align them as they are or enable size matching for a cleaner shared edge. Avoid stretching; preserve each image aspect ratio when resizing.

Are my photos uploaded to iTextMaster?

During normal use, iTextMaster Image Merger reads, arranges, and exports the images locally in your browser, so the source files do not need to be uploaded to a server.

Can I merge more than two images?

Yes. iTextMaster Image Merger supports up to 20 images in Horizontal, Vertical, Grid, or Freestyle layouts.