Which is open source or free online key frame editor?

There are several open-source or free online keyframe editors that you can use for video editing. Here are some popular options:

**OpenShot**: An open-source video editor that supports keyframing and provides a user-friendly interface. It’s compatible with Windows, macOS, and Linux.

**Shotcut**: Another open-source video editor that offers extensive features, including keyframe animation for video effects and filters. It is also cross-platform (Windows, macOS, and Linux).

**Blender**: While primarily known for 3D modeling and animation, Blender includes a powerful video sequence editor that supports keyframing for video editing. It’s available on all major operating systems.

**Kdenlive**: A free and open-source video editor tailored for Linux but also available on Windows and macOS. It features a timeline-based editing system and supports keyframing.

**DaVinci Resolve**: Although the free version is not open-source, it offers a robust set of video editing features, including keyframing. It’s widely used in the industry and is available for Windows, macOS, and Linux.

**Kapwing**: While primarily an online video editing tool, Kapwing offers free features with a user-friendly interface, though it has limitations on export quality and duration unless you sign up for a subscription.

**WeVideo**: An online video editor that provides both free and paid plans. The free tier has some limitations but allows for basic editing and keyframe animations.

Make sure to check the individual features, limitations, and system requirements of each tool to find the one that best suits your needs!