This tool expands the segments of a file in one or both directions. It can also flatten a segment to its start, middle or end point before expading. If a strand column is specified, upstream and downstream expansion are defined in relation to the strand direction.

• Select the genome
• Select the file you to expand.
• Select whether you want to treat the track as segments, or as start, middle or end points. Such conversion is done before any expansion or contraction is carried out.
• Type in the number of base pairs you want to expand the segments in upstream and downstream direction. Contraction is performed by specifying negative values. A shortened format, specifying mega- and kilobases with "k" and "m", respectively, is supported.
• Select whether you would like to remove segments that, after expansion, crosses chromosome border, or just crop them.
• Click execute.

See full example of how to use this tool.