DNA test vs facial AI: which to choose for family resemblance?
You want to know who your child looks like, or understand your family heritage? Two very different technologies answer this question: DNA tests (23andMe, MyHeritage, AncestryDNA) and facial AI like Look Like Me. Here is an honest comparison.
What each tool actually measures (it is not the same)
First essential point: these two tools do not answer the same question, even though they are often confused.
- DNA tests analyse your genome (between 600,000 and 700,000 SNP markers). They tell you where you come from (geographic origins), which genes you carry (eye color, medical predispositions) and identify your biological cousins. This is genetic genealogy.
- Facial AI analyses your face (and your parents') via thousands of reference points computed by a deep learning model (ArcFace, FaceNet). It tells you who you visually resemble and how strongly. This is comparative biometrics.
Consequence: if your goal is "to know if my child really has dad's eyes", AI is more direct. If your goal is "to discover where my ancestors come from", a DNA test is mandatory.
Detailed comparison: price, delay, accuracy, privacy
On accuracy: the myth of the "absolute DNA test"
DNA tests are extremely accurate on what they measure: your genetic code. But their accuracy on visual resemblance is a myth: no DNA test in the world will tell you "you look 80% like your father". It will tell you "you share 50% of your DNA with him", which is mathematically true for every child, regardless of visible resemblance.
Facial AI, on the other hand, measures exactly what we are asking: perceived visual similarity. Its margin of error (~10-15%) comes mostly from photo quality (light, angle, expression). With 3 decent photos, the score is very close to human perception.
Bottom line: for the question "who does my child look like", AI is the right tool. For the question "where do my ancestors come from", it is DNA.
Privacy: the most divisive choice
This is where the two technologies diverge the most.
DNA test: your saliva sample contains your entire genetic code, that is 3 billion base pairs. Once sent, the company can potentially (depending on its TOS):
- Sell anonymised genetic data to pharmaceutical labs (documented case at 23andMe in 2018 — GSK partnership).
- Keep the physical sample for 1 to 10 years depending on jurisdiction.
- Be targeted by hackers: 23andMe had a 6.9 million-account breach in 2023.
Facial AI Look Like Me: your photos are kept 12 months max (with email reminders 7 days and 1 day before deletion), deleted within 1 hour in guest mode, and embeddings (facial vectors) are never persisted — they are computed in memory during the analysis, then forgotten. EU hosting compliant with GDPR.
It is not that DNA is necessarily bad — it is that its risk surface is intrinsically larger. For serious genealogy, the risk is worth it. For having fun seeing if baby has dad's eyes, it is overkill.
Which tool for which need? Our recommendation
To help you choose:
- You just want to know who your baby or child looks like → Facial AI. Fast, free for the first test, and exactly what you are asking.
- You are looking for your origins, cousins, or a medical risk (BRCA, hemochromatosis...) → DNA test mandatory.
- You are intrigued by both → Start with AI (free, 30 seconds). If the resemblance makes you want to go further, the DNA test adds the genealogical dimension.
- You want to give an original gift → AI Gift Pack from Look Like Me (€3.99). More accessible and more immediate than a $99 DNA kit.
The two technologies are complementary, not competing. But for 80% of everyday family questions, facial AI is more than enough — and you do not need to spit in a tube.
❓ Frequently asked questions
Can a DNA test tell me who my child looks like?
No, not directly. The DNA test tells you that your child shares ~50% of their DNA with each parent — which is true for every child, regardless of visible resemblance. To measure perceived resemblance, facial AI is the right tool.
Does Look Like Me sell data like some DNA tests?
No. No data is shared with third parties for commercial purposes. Photos are deleted within 12 months (1 hour in guest mode) and facial embeddings are never kept. EU hosting, GDPR compliant.
Is AI as accurate as DNA?
For perceived visual resemblance, yes — often more, actually, because it measures exactly what the human eye perceives. For genealogy or medical markers, no: DNA is unmatched for those uses.
How much does a typical DNA test cost?
Between $79 (basic 23andMe or MyHeritage kit on sale) and $199 (full kit with medical report). Count 3-6 weeks of delay, and additional cost if you want to test multiple family members.
Can I do both?
Yes, they are complementary. Many of our users start with Look Like Me AI for their family resemblance, then do a DNA test if genetic curiosity pushes them further.