There are many splice site mutation prediction sites you can try like NNSPLICE, MaxEntScan, AnalyzerSpliceTool, Splice Site Score, Human Splicing Finder v 3, RegRNA and many more. However I like HSF most. You can explore. http://www.umd.be/HSF3/index.html.... Just check..

Ultimately you might also wish to perform an actual physical method if you find that your splice mutation is an interesting one.. You can check whether the quantitative or size of the transcript (mRNA) differs from wild type vs mutant form.

Note that predictions are always only predictions. Never proof.

Aside from that, if the mutation affects the core splice site (GT/AG), an effect on splicing is very likely. Deep intronic mutations are a lot more difficult to predict.