How does this remove interlacing?

This category's shared GIF decoder already reads the Image Descriptor's interlace bit for every frame and reorders 4-pass interlaced pixel data back into normal top-to-bottom rows as a routine part of decoding, before compositing frames. So this tool simply decodes the file (which produces correctly-ordered pixels regardless of the input's interlace bit) and re-encodes it with the shared encoder, which never sets the interlace bit.

What happens if I upload a GIF that wasn't interlaced to begin with?

Nothing changes visually or structurally in a meaningful way, it's simply decoded and re-encoded as a normal, non-interlaced GIF, a harmless no-op in practice.

Does de-interlacing lose any image quality?

No. Interlacing only affects the storage order of a frame's rows, not any pixel value, so reversing it doesn't discard any visual information beyond the same 216-color palette quantization every tool built on this category's shared encoder applies.

Does this affect animation timing or frame count?

No, every frame's delay and the file's loop count are preserved exactly as decoded; only each frame's internal row storage order changes.

Interlaced to Non-Interlaced GIF Converter

Overview

Introduction

Some old or specially-encoded GIFs store their pixel rows in GIF89a's 4-pass interlaced order, a holdover from dial-up-era progressive rendering, that some tools or pipelines expect to be plain top-to-bottom order instead.

This tool converts any GIF back to standard row order, decoding and re-encoding it entirely in the browser.

What Is Interlaced GIF to Non-Interlaced GIF Converter?

A GIF-to-GIF converter that guarantees non-interlaced output: it decodes the uploaded file (this category's shared decoder already de-interlaces any interlaced frame data as a normal part of decoding) and re-encodes every frame with the shared encoder, which always writes plain top-to-bottom row order.

It's the direct inverse of Non-Interlaced GIF to Interlaced GIF Converter.

How Interlaced GIF to Non-Interlaced GIF Converter Works

The uploaded GIF is decoded frame-by-frame: each Image Descriptor's interlace bit is read, and if set, that frame's LZW-decompressed pixel data is reordered from the 4-pass interlace sequence back into normal row order before being composited onto the canvas.

The fully-decoded, correctly-ordered frames are then re-encoded as a standard GIF89a file via this category's shared encoder, which quantizes to the shared 216-color palette and writes plain (non-interlaced) row order with no special flags.

When To Use Interlaced GIF to Non-Interlaced GIF Converter

Use it when a downstream tool, pipeline, or hand-written parser can't handle interlaced GIFs and you need to normalize an uploaded file's row order first.

Also useful for confirming what an interlaced GIF actually looks like once fully rendered, without needing a specialized progressive-rendering viewer.

Often used alongside Non-Interlaced GIF to Interlaced GIF Converter and GIF to Sprite Sheet Converter.

Features

Advantages

Works correctly regardless of whether the input was interlaced or not, since decoding always produces correctly-ordered pixels either way.
Reuses this category's already-proven shared decoder and encoder rather than a bespoke, separately-tested parsing path.
Preserves every frame's delay and the file's loop count exactly.

Limitations

There's no indicator in the output showing whether the input actually was interlaced; running this on an already-normal GIF is a harmless but pointless re-encode.
Like every tool built on this category's shared codec, frames are re-quantized through a fixed 216-color palette, so subtle color banding is possible versus a source GIF with a finer original palette.

Examples

De-interlacing a progressively-rendering GIF

Input

old-banner.gif (interlaced, 1 frame, 468x60)

Output

old-banner-standard.gif (1 frame, 468x60, plain top-to-bottom row order)

The frame's rows, originally stored in the 4-pass interlace sequence, are read into correct top-to-bottom order during decoding and written back out that way during re-encoding.

Best Practices & Notes

Best Practices

If you specifically need to test or demonstrate interlacing, use this category's Non-Interlaced GIF to Interlaced GIF Converter instead; this tool only ever removes it.
Don't expect any visible difference from a fully-loaded viewing perspective; the effect is only observable during a slow, progressive download.
Verify frame count and delays are unchanged afterward if you're relying on this as part of an automated pipeline.

Developer Notes

This tool intentionally contains almost no bespoke logic: it's a thin `decodeGif` -> `encodeGif` pass-through, since the shared decoder's existing interlace-bit handling (reading the Image Descriptor's 0x40 flag and reordering via its internal 4-pass `deinterlace` step) already does the real work, and the shared encoder never writes the interlace bit itself.

Interlaced GIF to Non-Interlaced GIF Converter Use Cases

Normalizing an interlaced GIF's row order before feeding it into a tool or pipeline that only handles standard row order
Confirming an interlaced GIF's fully-rendered appearance without a progressive-rendering-aware viewer
Cleaning up old, dial-up-era interlaced GIFs as part of an asset-modernization pass

Common Mistakes

Assuming this tool will report whether the input actually was interlaced; it doesn't detect or display that, it simply guarantees non-interlaced output either way.
Expecting a visual or file-size change from de-interlacing an already-normal GIF; the re-encode is effectively a no-op in that case.

Tips

If you're unsure whether a GIF is interlaced, most image viewers and editors show this in their file-info panel before you convert it.
Pair with GIF to Base64 Converter or GIF to Data URL Converter afterward if you need the normalized file embedded as text.

Interlaced GIF to Non-Interlaced GIF Converter