DNA File Checker
Is your raw DNA file complete, damaged, or in the wrong genome build? Drop it below for a verdict in seconds: chip, build (GRCh37 or GRCh38), call rate, missing chromosomes, Excel damage and duplicates. It is the new version of our Chip Identifier, still 100% client-side: your file is never uploaded to our servers.
Drop your RAW DNA file here
or click to browse
❓ How do I find my raw DNA file?
Frequently asked questions
Is my DNA file corrupted?
Drop it in the checker above and read the verdict. A healthy raw file covers chromosomes 1 to 22 (usually X too, often Y and MT), ends on a complete line, has whole-number positions and plain-letter genotypes, and a call rate above 95%. Most damage comes from an interrupted download, or from opening the file in Excel and saving it: Excel can cut it at 1,048,576 rows, write positions as 1.23E+05, turn values into dates or wrap lines in quotes. If the checker says DAMAGED OR INCOMPLETE, download a fresh copy from your testing company and upload it untouched (the .zip is fine).
What is the difference between GRCh37 and GRCh38?
They are two versions of the human reference genome. The same SNP keeps its rsID and genotype, but its position number is different in each build. 23andMe, AncestryDNA, MyHeritage, FamilyTreeDNA and Living DNA deliver GRCh37 (also called hg19 or build 37), which is what most tools expect. Files converted from sequencing data are sometimes GRCh38 (hg38). The checker compares 263 reference markers with their verified positions in both builds (dbSNP) and only names a build when the evidence is clear. If your file is GRCh38, our Genome Build Liftover converts it to GRCh37.
Why does my DNA file have so many no-calls?
A no-call (written -- or 0 0) is a marker the chip could not read with confidence. Every file has some: up to about 5% is normal. A higher rate usually comes from a weaker saliva sample, and results stay usable down to about 92%, just slightly less precise. Below 80% the sample partly failed and your testing company may offer a re-test. Y markers are mostly no-calls in files with an XX profile, and MT markers are left empty by some exports: that is expected and does not count against your file.
Is this the old Chip Identifier?
Yes. The DNA File Checker is the new version of our Chip Identifier: it still tells you your chip (23andMe v1 to v5, AncestryDNA v1 and v2, FTDNA, MyHeritage, Living DNA), SNP count, call rate and coverage for our tools, and now adds the file health check on top.
Is my DNA uploaded anywhere?
No. The whole check runs in your browser with JavaScript. The file is read on your device and nothing is sent to our servers or stored.