Snapping all keysframes to a full frame

One of my BeatEdit users just had the same question, since beat markers and keyframes generated by BeatEdit in sync with the beat have subframe accuracy and he didn't ant that for some reason.

I noticed that the script above suggested by Airweb does not preserve the keyframe easing. Therefore I created tools for my (paid) extension Automation Blocks for After Effects now, which can snap both markers and keyframes to frame boundaries (and preserve all marker details and keyframe easing):

Keyframes are always based on time. When you change the frame rate, they may not line up with the start of a frame, but the change in value will still happen at the same time, rounded to the nearest frame. Snapping a keyframe to the start of a frame will not change the animation's timing or appearance. The only thing that will change is the position of the keyframe relative to the start of the frame. Snapping every keyframe will not change the rendered movie's timing or look. In my opinion, it's a waste of time. 

Movies that were shot on film at 24 fps and broadcasted at 29.97 fps still look like movies instead of videos.

Try this, you can select multiple properties at once:

AdjustKeyframesToComposition.jsx

var proj = app.project;
var thisComp = proj.activeItem;
var props = thisComp.selectedProperties;
if (!props.length) {
  alert('Please select at least 1 property.');
} else {
  app.beginUndoGroup("undo");

  for (var propIndex = 0; propIndex < props.length; propIndex++) {
    var prop = props[propIndex];
    for (var keyIndex = 1; keyIndex <= prop.numKeys; keyIndex++) {
      var v = prop.keyValue(keyIndex);
      var t = Math.floor(thisComp.frameRate * prop.keyTime(keyIndex)) / thisComp.frameRate;
      prop.removeKey(keyIndex);
      prop.setValueAtTime(t, v);
    }
  }
  app.endUndoGroup();
}