Why a separate preview tool?
Most online Lottie viewers cap uploads at 5–10 MB and require an account. That works for vector-only animations a few KB in size, but the moment your file embeds PNG sequences from After Effects, you're in the 20–100 MB range — and those previewers give up before they begin.
The Lottie Preview tool above runs entirely in your browser. There is no server, no upload, no size limit. You can drop two files side-by-side to compare versions — for example, an original Lottie against a compressed one, or two iterations of an animation from your designer. Both players are synchronized so you can spot visual regressions the moment they appear.
Common workflows
1. Compression QA
After running a Lottie through the compressor, preview both files together to confirm the reduced version still plays correctly. Especially important when using aggressive presets like Smallest (q70 + frame skipping) on animations with subtle gradients or fine detail.
2. Designer-to-developer handoff
Designers can drop a candidate .json or .lottie file here before sending it to engineering, verifying playback in a neutral environment that matches what end users will see on the web.
3. A/B comparing animation revisions
When iterating an animation, the side-by-side player makes timing and easing differences immediately obvious — far more useful than playing each version separately in a player widget.
Privacy
The preview runs entirely in your browser using lottie-web. Your file is never transmitted to any server, including ours. You can use this on confidential pre-release assets without concern.