Free converter · no account · no upload
Convert 23andMe to FamilyTreeDNA format
Drop your 23andMe raw data export below and download it in FamilyTreeDNA format. Everything runs in your browser — no byte of your DNA leaves this device. The tool rewrites the file layout and nothing else.
Drop your raw DNA file here
or choose it from your device
Accepts the original .txt or .csv exports from 23andMe, AncestryDNA, MyHeritage and FamilyTreeDNA. Unzip a .zip first.
Private by construction: the file is read and rewritten locally with your browser's File API. There is no upload button and no network call — you can disconnect from the internet before choosing the file. Other online converters process your DNA on their server; this one cannot.
What actually changes from 23andMe to FamilyTreeDNA
These two files describe the same genotypes in different layouts. The conversion rewrites exactly this:
- The layout changes from a tab-separated .txt file to a comma-separated .csv file, with the FamilyTreeDNA column header.
- 23andMe writes a single letter where only one allele exists (male X and Y, mitochondrial DNA). The FamilyTreeDNA layout uses two-allele fields, so those rows are written as two identical letters — counted in the report.
What never changes: your rsIDs, positions, genotype letters and genome build. This is a format conversion — not a liftover, not imputation, not a "chip conversion".
| 23andMe | FamilyTreeDNA | |
|---|---|---|
| File extension | .txt | .csv |
| Column separator | tab | comma |
| Header row | # rsid ⇥ chromosome ⇥ position ⇥ genotype | RSID,CHROMOSOME,POSITION,RESULT |
| Chromosome naming | 1–22, X, Y, MT | 1–22, X, Y, XY, MT |
| No-call symbol | -- | -- |
Format compatibility is not platform acceptance
FamilyTreeDNA
FamilyTreeDNA's autosomal transfer still accepts uploads from the major providers, with version restrictions on their side (tests on some newer chips are not compatible). Their rules are theirs and can change.
Converter questions
Is converting to FamilyTreeDNA format the same as transferring my DNA to FamilyTreeDNA?
No. This rewrites your file's layout; whether any platform accepts an upload is that platform's decision, made by their own importer. The acceptance note above states what is publicly known — we never promise acceptance.
Does the conversion change my genotypes?
No. Genotype letters, rsIDs and positions are carried over byte-identical. Only the representation changes — delimiter, header, chromosome naming and the no-call symbol — and every such change is counted in the report.
Why is this free, with no upload?
Because it costs us nothing to run — your browser does the work — and it is how we would want our own DNA handled. Our paid product is the analysis of what is inside the file, and it is entirely separate from this tool.
Want to know what is actually in that file?
Run the free analysis: your variants matched against ClinVar, PharmGKB and the GWAS Catalog, with the free findings shown before any purchase. One-time payment for the full report — no subscription.
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