DIOPT lets you view ortholog predictions from several tools at one time. The number of tools predicting a given ortholog pair serves as a measure of confidence in the orthology relationship. Click "alignment & scores" to view protein alignments and detailed info for a given pair.
A tutorial that explains scores, ranks, and 'best' matches is available at YouTube.
Please visit the DIOPT documentation page.
You might also be interested in our DIOPT-Diseases & Traits (DIOPT-DIST) tool, which takes ortholog matches to human genes a step further, asking if those human genes have been associated with human diseases. DIOPT-based ortholog searches are also now supported at FlyBase.