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Lizely

GIF Optimizer

Re-encode a local animated GIF with a smaller palette while showing the actual output size instead of promising a result.

Fewer colors can reduce the file size but may visibly simplify gradients. Results can be larger for some source GIFs.

Privacy: your files never leave your device. All processing happens locally in your browser.

How to use

  1. 1.Choose an animated GIF up to 20 MB and select a palette size of 256, 128, or 64 colors.
  2. 2.Select Optimize GIF and let the browser re-encode the complete visible frames locally.
  3. 3.Compare the shown original and output sizes, download the result, and review a complete animation loop.

About GIF Optimizer

GIF Optimizer creates a new animated GIF from a file you choose in the browser. Select a GIF, choose a palette size of 256, 128, or 64 colors, and run the local optimization. The page decodes the animation, rebuilds each visible frame, re-encodes it with the selected palette limit, and reports the original and resulting byte sizes before offering a download. Your GIF, decoded pixels, and output file remain in the current browser tab; no upload, account, server queue, or cloud storage is involved.

The word optimizer needs a careful definition. GIF is already a compressed palette-based format, so there is no universal transformation that makes every GIF smaller without tradeoffs. This tool changes one explicit variable: the maximum number of colors available to each output frame. A lower palette can reduce the color table and sometimes simplify the pixel index stream. It can also introduce banding, altered dithering, or a larger file when the new palette layout compresses less efficiently. The page therefore displays the real before-and-after sizes and explicitly allows a positive percentage change. It never labels a larger output as a saving.

Animations can contain partial updates rather than one full picture per frame. Re-encoding those patches blindly can show the wrong background on a later frame, especially when transparency or disposal behavior is involved. Before palette quantization, the tool composes every image block into the complete visible logical canvas. It keeps the decoded frame order and per-frame display delays, then encodes those full canvases. This produces a consistent, viewable result even if the original GIF relied on tiny changed rectangles to save space. The tradeoff is intentional: a source that was already highly optimized with partial frames can grow after full-frame re-encoding.

Choose 256 colors when preserving as much color detail as possible matters more than aggressive reduction. Choose 128 colors for many illustrations, UI animations, or screen recordings with moderate color variety. Choose 64 colors for simple drawings, flat graphics, or a more forceful experiment where visible simplification is acceptable. These are output controls, not claims about the source's original color count. Inspect gradients, photos, fine text, and transparency edges at their actual destination size after downloading. A low color count can make an animated photo look substantially different even when the byte size improves.

The browser applies limits before allocating the complete output work. A selected GIF can be up to 20 MB, with a canvas no larger than 4,096 pixels on either side and three million pixels per frame. It accepts no more than 50 image frames and constrains aggregate patch and output pixel budgets. A compressed animation may expand into much more memory than its file size suggests, so an input outside those bounds is rejected with a clear error rather than leaving a partial or stale download.

The export is a new GIF stream. It retains the decoded visible frame sequence and delays, but it does not preserve the source's palette tables, comment blocks, application extensions, byte-level optimization method, or a finite loop count. The result is configured to repeat continuously. GIF supports one-bit transparency, and transparent output pixels are encoded within that model. The tool does not convert the GIF to video, retain audio, create WebP or MP4, trim frames, change speed, remove duplicate frames, or optimize a video file.

For a practical workflow, keep the original GIF, start at 128 colors, download the result, and compare one full loop side by side with the source. If the colors are acceptable, compare the actual byte count. Try 64 colors only if visual quality remains suitable. If the result becomes larger or looks worse, use the original or choose a different format for the destination rather than assuming a palette reduction must help. Social networks, messaging apps, and CMS platforms can reprocess GIFs again after upload, so test the final published asset as well.

The page uses standard browser canvas and local Blob download APIs. Browser rendering and color management can differ slightly, and a damaged or unsupported GIF may fail before output. In that case the tool stops with an error and keeps no old output masquerading as a new result. It is designed for transparent, inspectable local re-encoding rather than an opaque compression promise.

Methodology & sources

Validate a bounded local GIF, compose partial frame patches into full visible canvases, quantize each output frame to the visitor-selected 256, 128, or 64 color palette, retain decoded frame delays, show the actual size delta, and export a new local GIF Blob without claiming a guaranteed saving.

Frequently asked questions

Will optimization always make my GIF smaller?
No. Palette reduction can help, but a new full-frame encoding can also be larger. The page reports the actual size change.
Which palette size should I choose?
Start with 128 colors, use 256 for more color detail, and try 64 only when stronger simplification is acceptable after visual review.
What animation behavior is retained?
The decoded visible frame order and per-frame delays are retained, but the output is a new continuously looping GIF without original metadata or finite loop settings.
Is my GIF uploaded for optimization?
No. The GIF is decoded, composited, quantized, encoded, and downloaded in the current browser tab.

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