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FASTA analyser
Analyse a whole multi-FASTA file at once: every record's length, GC content and molecule type, with dataset-level statistics including N50 — and a CSV download for your records.
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Per-sequence results
Good to know
What N50 means
N50 is the length of the shortest sequence in the set of longest sequences that together cover at least half the total length. It is the standard quick quality number for assemblies and sequence collections.