About

A reader for your raw DNA file

Sequencings reads the raw data file that 23andMe, AncestryDNA, MyHeritage and Family Tree DNA let you download, and it does so inside your browser. The file is never sent to us.

How it works

The page reads your file with the browser's own file API, parses it in memory and forgets it when you close the tab. There is no upload endpoint on this site and no account to create, which you can check yourself in the network tab of your browser's developer tools while a file is being read. The 10 free markers ship with the page; the full set of 108 is sent to your browser after a one-off payment, so data travels to you, never from you.

Each marker is checked against Ensembl GRCh37 coordinates, genotypes are resolved for strand before they are read, and markers whose two alleles are complements of each other (A/T and C/G), which no consumer file can orient, are declined rather than guessed. The full detail, with every source and its retrieval date, is on the method page.

What it will not tell you

A consumer chip reads about 650,000 of the genome's 3,100,000,000 positions, roughly 0.02 per cent, chosen because they are common rather than because they are medically important. Rare disease variants are where raw-file readings go wrong: in a study of 49 samples (Tandy-Connor et al., False-positive results released by direct-to-consumer genetic tests, Genetics in Medicine (2018)), 40 per cent of variants flagged in raw files were false positives on clinical confirmation. So this site does not report rare pathogenic variants at all, and nothing it shows is a diagnosis or medical advice. See the medical disclaimer.

Corrections and contact

Corrections and enquiries are handled by Nikko Salamanca. If you think a result or a source is wrong, use the contact form and name the marker; it is either changed or the reason it stands is explained.

Pricing and refunds are on the pricing page and in the terms; what is and is not collected is in the privacy policy.