Raw DNA Data Explained: What It Is and Why to Download It

Every major consumer DNA test gives you the option to download your raw data. Most users never do. The download is one of the most useful and most overlooked features in the entire category, and it costs nothing.

What raw DNA data actually is

Your raw data file is a plain text file. Each row is one position in your genome that the company’s genotyping chip checked, and the row records which letters you have at that position. For a SNP-genotyping test, the file typically contains entries for several hundred thousand positions. According to 23andMe’s product technology documentation, their array covers roughly 600,000 to 700,000 SNPs. AncestryDNA’s array is broadly similar in scale. So is MyHeritage’s. The exact set of positions varies between companies and between chip versions within a company.

A line in the file looks something like this:

rs4477212    1    82154    AA

That is the SNP identifier, the chromosome, the position on the chromosome, and your genotype (two letters because you have two copies of each chromosome, one from each parent). Multiply by several hundred thousand and you have your file. For the underlying mechanics, see how DNA tests work.

Whole-genome sequencing files are a different beast. They are much larger (typically tens of gigabytes) and use different formats like FASTQ, BAM, or VCF. Most of this guide is about SNP-genotyping raw data, which is what the big four consumer tests provide.

Why you should download it

Three reasons, in order of importance.

1. It hedges against the company changing. Companies retire features, change terms, raise prices, restructure, and occasionally go out of business. 23andMe filed Chapter 11 in March 2025; its assets were transferred to TTAM Research Institute in mid-2025. Nebula Genomics shut down its consumer service in February 2025. Customers who had downloaded their raw data kept the underlying value of their test. Customers who relied on the dashboard alone had a much worse experience. Our genetic data privacy guide covers the broader implications.

2. It lets you fish in additional databases for free. Several services accept free uploads of raw data from other companies and run their matching against their database. This is the single best way to get more relative matches without buying more kits. More on that below.

3. It opens up third-party analysis tools. Once you have the file, several services (some free, some paid) will generate additional reports from it: more detailed ethnicity breakdowns, deeper trait reports, and various health and wellness analyses. The quality of these tools varies widely. Treat them with the same skepticism you would apply to the original company’s reports.

For the broader buyer’s framework, see the guide to DNA testing pillar.

How to download it from each company

The process varies in detail but follows the same pattern. Log in, find the raw data section (usually under settings, account, or DNA), confirm your password, and request the download. Files are typically delivered as a download or an emailed link. They arrive as a compressed text file (.txt.zip or .csv.zip) of roughly 5 to 25 megabytes.

• AncestryDNA: Account settings, then DNA, then download raw DNA data. Requires password confirmation and email verification.
• 23andMe: Browse raw data section, then download. Note that ongoing changes to 23andMe’s operations may affect this flow; download yours sooner rather than later if you tested there.
• MyHeritage DNA: Manage DNA kits, then download.
• FamilyTreeDNA: Account, then download raw data.
• Living DNA: Settings, then raw data download.

Each company publishes step-by-step instructions on its support pages, and those are the authoritative reference because the interface changes.

Where you can upload it for free

This is where the raw data file pays for itself.

• MyHeritage DNA accepts free uploads from AncestryDNA, 23andMe, and others. Basic matching is free; some advanced tools require a one-time activation fee or a subscription.
• FamilyTreeDNA accepts free uploads from AncestryDNA, 23andMe, and MyHeritage for autosomal matching. Some advanced tools cost a small unlock fee.
• Living DNA accepts free uploads from 23andMe and AncestryDNA for an ancestry report.
• GEDmatch is a long-standing third-party service genealogists use for cross-platform matching, chromosome browsing, and a variety of analytic tools. Basic features are free; Tier 1 advanced features require a small monthly fee.

AncestryDNA does not accept uploads. It is the database you have to test into directly, which is why most genealogists start there and then upload to the others.

What to keep in mind before uploading

When you upload your raw data to a new service, you are sharing your DNA with another company, with that company’s privacy policy, terms of service, and data practices. Read the upload terms before you click. Decide whether you want to be visible in their matches list. Decide whether you consent to any research uses they describe.

GEDmatch in particular is the platform that was used in the 2018 Golden State Killer case, which surfaced the broader question of law enforcement access to consumer genetic databases. Its current consent regime gives users granular control over whether their data can be searched by law enforcement; the choice is yours to make consciously.

Storing the file

Save your raw data file somewhere you will find it again. A folder in your cloud storage labelled clearly, plus a local backup, is enough. The file is your DNA in text form; treat it with at least the same care you would give a tax return or a copy of your passport.

For what to do once you have results and the file in hand, see our guide on what to do after DNA test results.