Lightweight spackling is similar to joint compound, but much less dense and sticky. It is used to fill small holes up to about a quarter-inch in diameter, and is especially efficient for filling nail holes. It tends to be easier to spread and smooth than joint compound, since it is less sticky. Joint compound tends to shrink and change shape slightly as it dries, so it must be sanded before it can be painted. Serious cases of shrinkage may require a second coating of joint compound. Since lightweight joint compound does not shrink as much, it can be painted without sanding. Finally, lightweight joint compound dries much quicker than joint compound, and can be painted over in minutes rather than the hours it takes for joint compound to fully dry.
Vinyl spackling and joint compound are similar in terms of weight and consistency, and can both be used to repair large holes and fill depressions in the drywall. While vinyl spackling must be sanded before painting, it shrinks less than joint compound, and can provide smoother edges when filling large holes. Vinyl spackling is much more water resistant when it dries. While this means that it is less likely to be water damaged before it is topcoated, it also means that it cannot be smoothed or feathered with a damp sponge as easily as joint compound.
Spackling is available in formulations that provide advantages over joint compound in specific situations. Color change spackle is pink or purple when it is first applied, and dries to white when it is ready to be painted. Spackle with mildewcide is available for use in high-moisture environments. Exterior spackle can perform outdoor repair jobs for which joint compound is unsuitable.
Spackling is formulated to be pH neutral, while joint compound is not. Joint compound must be primed before certain oil-based paints are applied or it will discolor the paint on top of the joint compound. Oil-based paint may be applied directly to spackling without discoloration occurring.