How do I merge multiple GIFs into one?

Upload two or more GIF files using the Convert Media GIF Merge tool. Once uploaded, choose your merge mode — Sequential to play them one after another, Horizontal to place them side by side, or Vertical to stack them. Click Merge and the combined GIF will be ready to download in seconds. Everything runs in your browser with no uploads to any server.

How many GIFs can I merge at once?

Convert Media supports merging up to 10 GIF files in a single operation. After uploading your initial batch, you can add more GIFs using the "Add more" button as long as you are under the 10-file limit. You can also reorder the files before merging using the up and down arrow controls.

What is the difference between sequential and side-by-side merging?

Sequential merge plays GIFs one after another in time — the first GIF plays fully, then the second begins. Side-by-side (horizontal or vertical) merge plays all GIFs simultaneously in the same frame, either placed next to each other horizontally or stacked vertically. Sequential is best for multi-part animations; side-by-side is best for comparison layouts and split-screen effects.

Why does my merged GIF have black bars?

Black bars appear when GIFs have different dimensions and you use horizontal or vertical merge mode. For horizontal stacking, all GIFs need the same height. For vertical stacking, all GIFs need the same width. FFmpeg automatically pads mismatched GIFs with black. To avoid this, use the GIF Crop or GIF Optimizer tools to standardize dimensions before merging.

Is there a file size limit for merging GIFs?

Individual GIF files can be up to 100MB each. However, practical limits depend on your browser and device memory. Merging many large, high-resolution GIFs may require several hundred megabytes of RAM. For large merges, consider optimizing individual GIFs first using the GIF Optimizer to reduce their size before combining them.

GIF Merger

Combine multiple GIFs into one animation. Sequential, side-by-side, or stacked — all processed in your browser.

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Drop a video file here, or click to browse

Supports MP4, WebM, AVI, MOV, MKV and more

Max file size: 2GB (recommended: under 200MB)

Combine GIFs Into One Seamless Animation

Everything you need to know about merging multiple GIF files, from choosing the right merge mode to optimizing the output.

What Is GIF Merging and When Should You Use It?

GIF merging combines two or more animated GIF files into a single output. Depending on the merge mode you choose, the GIFs can play one after another, appear side by side, or stack vertically. This makes GIF merging useful in a wide range of scenarios: combining animation sequences, creating comparison panels, building multi-step tutorial loops, and assembling animated storyboards.

Convert Media handles GIF merging entirely in your browser using FFmpeg WebAssembly. No uploads, no servers, and no privacy risks. You can merge up to 10 GIF files in a single session, reorder them, and choose between three spatial or temporal merge modes before generating the final output.

Understanding the Three Merge Modes

Sequential — One After Another

Sequential mode concatenates GIFs in time. The first GIF plays completely, then the second begins, and so on until all GIFs have played. The output dimensions match the first GIF in the sequence. This mode is ideal for multi-part animations, story sequences, step-by-step tutorials, and looping playlists. The resulting GIF loops back to the beginning after the last clip ends.

Horizontal — Side by Side

Horizontal mode places all GIFs side by side in a single wide frame. All GIFs play simultaneously. This mode works best for comparison animations, split-screen demos, before-and-after effects, and showcasing variations of the same animation. For best results, use GIFs with the same height. If heights differ, FFmpeg will pad the shorter ones to match.

Vertical — Stacked

Vertical mode stacks GIFs on top of each other in a tall frame. All GIFs play simultaneously. This is useful for stacking animation panels, displaying parallel processes vertically, and creating multi-row animated layouts. For best results, use GIFs with the same width. If widths differ, FFmpeg will pad the narrower ones to match.

Tips for the Best Merge Results

Match Dimensions Before Merging

For horizontal and vertical modes, mismatched dimensions cause automatic padding with black bars. To avoid this, pre-process your GIFs to the same width (for vertical stacking) or the same height (for horizontal stacking) using the GIF Optimizer or GIF Crop tools before merging. This gives you full control over the final frame dimensions.

Order Matters in Sequential Mode

The playback order is exactly the order shown in the file list. Use the up and down arrow buttons to reorder GIFs before merging. The first GIF's dimensions set the frame size for all subsequent clips in sequential mode, so put your primary GIF first if they have different dimensions.

Keep Frame Rates Consistent

GIFs with different frame rates can produce uneven playback in sequential mode or misaligned frames in horizontal and vertical modes. For best results, use GIFs with the same or similar frame rates. If your source GIFs have different frame rates, use the GIF Optimizer to normalize them before merging.

Watch Output File Size

Merging GIFs combines their frames, so the output file will typically be larger than any individual input. Horizontal and vertical merges multiply the pixel count by the number of GIFs placed side-by-side or stacked, which increases file size significantly. If the output is too large, consider reducing the dimensions of source GIFs first using the GIF Optimizer.

Related GIF Tools

Prepare and post-process your GIFs with these tools before and after merging:

GIF Optimizer

Reduce file size before merging

GIF Crop

Match dimensions for clean merges

GIF Splitter

Extract individual frames

Frequently Asked Questions

Everything you need to know about Convert Media.