GTF TO GFF3 Converter
The GTF TO GFF3 converter is designed to make it easier to transform common forms of GTF into valid GFF3. This server will handle up to chromosome sized GTF files, if you need to convert genome size gtf files we encourage you to checkout the gtf2gff3 perl script from the SO CVS archives for local use.
You can learn more about the GTF 2 GFF3 converter by reading the README document included with the gtf2gff3 perl script. This converter and it's default configuration file have been tested on Ensembl and Twinscan GTF, and it should work on other GTF files that follow the same format as either of those. It does not work on GTF from the UCSC table browser because those files use the same ID for gene and transcript, so it is impossible to group multiple transcripts to a gene. If you would like to modify the config file for use on other GTF/GFF formats use the default config file as a template