The Basic Local Alignment Search Tool (BLAST) finds regions of local similarity between sequences. The program compares nucleotide or protein sequences to sequence databases and calculates the statistical significance of matches.
Standard Nucleotide BLAST BLASTN programs search nucleotide databases using a nucleotide query. more...
This title appears on all BLAST results and saved searches. Enter one or more queries in the top text box and one or more subject sequences in the lower text box. Then use the BLAST button at the bottom of the page to align your sequences.
Smart Blast searches a protein query against the landmark database Enter Protein Query Sequence
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BLAST (Basic Local Alignment Search Tool) is a tool that compares nucleotide or protein sequences to sequence databases. It is extensively used to identify sequence similarity and homology, thereby helping researchers infer the function and evolutionary relationships of sequences and identify the members of gene families.
BLAST can be used to infer functional and evolutionary relationships between sequences as well as help identify members of gene families. There are several types of BLAST searches.
BLAST is also often used as part of other algorithms that require approximate sequence matching. BLAST is available on the web on the NCBI website. Different types of BLASTs are available according to the query sequences and the target databases.