Duonym: AI Baby Names

Duonym is a baby name app for two people, built on two machine-learning models you can actually inspect. HOW IT WORKS You and your partner each swipe through names — nope, ok, or shortlist. Every swipe refits a model of your individual taste. When you both love the same name, it's a match. You can start swiping immediately as a guest. No account, no email, no paywall. THE PREFERENCE MODEL A Bayesian ordinal logistic regression over 105 features per name: length, syllable count, vowel structure, popularity across decades, trend direction, and a learned embedding that captures how names relate to one another. Ordinal, because "ok" genuinely sits between "nope" and "love it". Treating that as a yes/no throws away half of what you told it. It refits after every single swipe. No batching, no waiting for tomorrow's recommendations. THE PHONETIC MODEL Add your surname and a second model scores how each first name flows into it — a pairwise ranker over 93 phoneme-boundary, rhythm and overlap features, built on the 125,162-entry CMU Pronouncing Dictionary. It is deliberately blind to popularity, gender, prestige and anything private about you. It only listens to how the two names sound together. One slider controls the blend: pure taste, pure sound, or anywhere in between. SEE WHAT IT LEARNED Open the AI Transparency panel and you get the actual fitted weights — which themes push a name up for you, which push it down, and by how much. Separately for each partner. It is not a personality quiz. They are the model's coefficients. WHAT ELSE • 19,472 names, filtered for clearly negative associations if you want • Every swipe reviewable and reversible — change your mind and the model refits • Hear any name spoken, with or without your surname • Meanings, origins and notable bearers, sourced from Wikidata and Wikipedia • A "model detail" slider — broad patterns or fine distinctions, your call • Keeps 200 recommendations on your device, so it works on the Underground • Shortlist together, then share one link for friends and family to vote FOR THE PARTNER WHO ASKS "BUT HOW DOES IT KNOW" It doesn't scrape your contacts, guess from your Instagram, or send your data to a language model. It fits a small, well-understood statistical model to the choices you explicitly made, and then it shows you the fit. The phonetic model was trained on 3,018 human ratings across 288 surnames, with surnames held out between training and evaluation so it cannot memorise them. It scores 0.80 pairwise accuracy on the held-out split. We publish that number rather than a rounder one because you are the sort of person who would check. PRIVACY Free. No advertising. No selling data. No in-app purchases. Swipe as a guest without an account at all. If you do sign in, you can delete your account and everything derived from it from inside the app, in Settings, in two taps. Privacy policy: https://duonym.web.app/privacy Terms of use: https://duonym.web.app/terms Support: https://duonym.web.app/support