What kind of randomness does this use?

A Fisher-Yates shuffle driven by `crypto.getRandomValues()` with rejection sampling, the same `secureRandomInt` helper this codebase's `random` category already uses, rather than `Math.random()`. This avoids any modulo bias in the resulting shuffle.

Do frames keep their own original delays after shuffling?

Yes, each frame's delay travels with it; only the order changes, not the timing associated with any individual frame's content.

Is there a minimum number of frames required?

Yes, at least 2, since a single-frame GIF has nothing meaningful to shuffle.

Can I get the same shuffle result twice in a row?

Not predictably. Every run draws fresh cryptographically random values, so re-running the tool on the same GIF will generally produce a different order each time.

GIF Frame Randomizer - Shuffle Animation Frames

Overview

Introduction

Want to see an animation's frames in a genuinely random order rather than picking one by hand? This tool shuffles them for you, using the same cryptographically strong randomness this codebase already relies on elsewhere.

Decoding, shuffling, and re-encoding all happen locally in your browser, so uploaded animations are never sent anywhere.

What Is GIF Frame Randomizer?

A frame-reordering tool that randomly shuffles an animated GIF's frame sequence using an unbiased, crypto-backed Fisher-Yates shuffle.

Unlike GIF Frame Rearranger, which needs a manually typed order, this tool picks the new order for you.

How GIF Frame Randomizer Works

The GIF is decoded into its frame array, then a Fisher-Yates shuffle draws its swap indices from `crypto.getRandomValues()` via rejection sampling (this codebase's `secureRandomInt` helper), avoiding the subtle bias plain modulo-based random draws can introduce.

The shuffled frames, each still carrying its own original delay, are re-encoded as a new GIF89a file with the original loop count.

When To Use GIF Frame Randomizer

Use it for a quick, genuinely random remix of an existing animation's frame order.

It's also handy for creating unpredictable glitch-art or randomized visual effects from an existing GIF's frames.

Often used alongside GIF Frame Rearranger, GIF Frame Duplicator and GIF Duplicator.

Features

Advantages

Uses cryptographically strong, rejection-sampled randomness rather than a potentially biased naive shuffle.
One click produces a fresh, unpredictable frame order with no manual index typing required.
Each frame keeps its own original delay, so timing still makes sense frame-to-frame even after shuffling.

Limitations

There's no way to reproduce or seed a specific shuffle result; every run is genuinely random and not deterministic.
Requires at least 2 frames; a single-frame GIF is rejected since there's nothing to shuffle.

Examples

Shuffling a 5-frame GIF

Input

5-frame GIF with frames in order 0,1,2,3,4.

Output

A new GIF with the same 5 frames in a randomly drawn order, e.g. 3,0,4,1,2.

A crypto-backed Fisher-Yates shuffle determines the new order; each frame keeps its own original delay wherever it lands.

Best Practices & Notes

Best Practices

If you want a specific, repeatable order rather than a random one, use GIF Frame Rearranger instead and type the order yourself.
Run the tool again if you don't like the first random result: every run produces an independent new shuffle.
Preview the shuffled result with GIF Frame Player before relying on it, since a random order can occasionally look very similar to the original by chance.

Developer Notes

This tool intentionally reuses the `random` category's `secureRandomInt` helper rather than `Math.random()` or this file's own bespoke RNG, keeping randomness behavior consistent across every tool in this codebase that needs an unbiased shuffle rather than maintaining a second parallel implementation.

GIF Frame Randomizer Use Cases

Creating a randomized remix of an existing animation's frame order for glitch-art or novelty effects
Quickly generating several different frame-order variants of the same source GIF to compare
Randomizing frame order as a lightweight obfuscation or randomization step before further editing

Common Mistakes

Expecting a reproducible result; this tool is intentionally non-deterministic and doesn't accept a seed.
Trying to shuffle a single-frame GIF, which the tool rejects since there's nothing meaningful to reorder.

Tips

Combine with GIF Duplicator afterward if you want a clean, re-saved copy of your favorite random shuffle result.
If you need a specific rather than random order, GIF Frame Rearranger gives you full manual control instead.

GIF Frame Randomizer