NCBI Sequence Link 1
NCBI Sequence Link 2
PCA Plot
Mutation Bar Plot
Analysis Log
About the NCBI FASTA Analyzer
The NCBI FASTA Analyzer compares FASTA sequences you supply, identifies the mutations between them, and renders the differences as a plot you can export. It is built for the everyday case of checking a sequence you received from NCBI, a sequencing provider, or a colleague against what you expected.
Paste or load two or more sequences, and the analyzer reports per-position differences, substitutions, insertions and deletions, together with summary statistics. From there you can export the plot as an image, the underlying data as CSV for a spreadsheet or downstream script, and a log file recording exactly what was analysed.
All comparison happens in the browser. Sequence data, including anything matching a human reference, is never uploaded.
What this tool does
Mutation detection
Identify substitutions, insertions and deletions between sequences and report their positions, so a discrepancy is a concrete finding rather than a suspicion.
Visual reporting
Render the comparison as a plot, which is far easier to include in a report or share with a collaborator than a wall of text output.
CSV export
Download the results as CSV for use in a spreadsheet, a figure, or a reproducible downstream analysis.
Log file export
Capture an analysis log documenting inputs, parameters and results, which is what makes the comparison defensible later.
Works with NCBI-derived FASTA
Handles the FASTA format returned by NCBI resources directly, so a retrieved record can be compared without editing.
Frequently asked questions
Are my sequences uploaded to a server?
No. The analysis runs entirely in your browser. Nothing you paste or load is transmitted or stored, which matters for human reference and clinical sequences.
What is the right workflow for checking a sequence I ordered?
Compare the delivered sequence against your expected construct or reference, check the mutations and their positions, then confirm anything unexpected against the sequencing trace before repeating the order.
How should I interpret a difference I did not expect?
First establish whether it is a real variant or an artefact. A substitution at a single position in a single read is usually sequencing error; a consistent change present across all reads at good quality is a genuine difference and may be a synthesis or cloning error.
Can I use this for human sequence data?
From a privacy standpoint yes, because nothing is uploaded. Be aware that a tool of this kind is an exploratory check and not validated clinical software, so it must not be the sole basis of a clinical conclusion.
What format should I input?
Standard FASTA with one or more records. Paste the sequence with its header, or load a .fasta or .fa file. Ambiguity codes such as N are treated as unknown rather than as a mismatch.
Related tools
All processing happens locally in your browser. Nothing you upload is transmitted or stored, as described in the privacy policy.