What it does

This tool counts the length of each fasta sequence in the file. The output file has two columns per line (separated by tab): fasta titles and lengths of the sequences. The option How many characters to keep? allows to select a specified number of letters from the beginning of each FASTA entry.

Example

Suppose you have the following FASTA formatted sequences from a Roche (454) FLX sequencing run:

>EYKX4VC02EQLO5 length=108 xy=1826_0455 region=2 run=R_2007_11_07_16_15_57_
TCCGCGCCGAGCATGCCCATCTTGGATTCCGGCGCGATGACCATCGCCCGCTCCACCACG
TTCGGCCGGCCCTTCTCGTCGAGGAATGACACCAGCGCTTCGCCCACG
>EYKX4VC02D4GS2 length=60 xy=1573_3972 region=2 run=R_2007_11_07_16_15_57_
AATAAAACTAAATCAGCAAAGACTGGCAAATACTCACAGGCTTATACAATACAAATGTAAfa

Running this tool while setting How many characters to keep? to 14 will produce this:

EYKX4VC02EQLO5  108
EYKX4VC02D4GS2   60