FASTA / FASTQ Statistics & Validator
Summarise and validate FASTA or FASTQ: counts, N50, GC, quality.
🌐 Runs on the SeqBench API — also callable via REST & MCP, and in bulk from the batch tools
Summarise and validate FASTA or FASTQ files with read count, total bases, min/max/mean/median length, N50, GC content and mean Phred quality. It provides a practical QC check for sequencing reads or assemblies without installing command-line tools.
Detected format: none
How to use the FASTA/FASTQ Stats tool
- 1Paste or drop in your FASTA or FASTQ content.
- 2Pick the Phred quality encoding (Phred+33 or Phred+64) for FASTQ.
- 3Read the summary statistics and any validation warnings.
Frequently asked questions
What is N50?
N50 is the sequence length such that half of the total bases are in sequences of that length or longer. It is a common summary of assembly or read-length distributions.
Which FASTQ quality encodings are supported?
Phred+33 (Sanger / Illumina 1.8+) and Phred+64 (older Illumina 1.3–1.7). Pick the encoding that matches your data.
Does it validate the file?
Yes. It flags missing '+' separators, sequence/quality length mismatches and malformed records.