Both are worn on the forehead to train your brain, but they measure different things. The Muse S Athena is the most complete consumer headset — it combines EEG with fNIRS, adds sleep tracking, and gives real-time audio neurofeedback. Mendi is deliberately simpler: fNIRS only (prefrontal blood flow), shown as a single game-like bar, with no subscription and almost no learning curve. It’s depth-and-versatility versus the easiest possible habit.
Muse S Athena or Mendi: which is better?
Higher ONDA score: Muse S Athena (8.5 vs 7.0)
Complete and rich vs simple and easy. The Muse S Athena wins on measurement (EEG + fNIRS), sleep tracking and versatility; Mendi wins on simplicity, price and habit-formation for pure focus training. Choose Muse for the fuller, more capable device; Mendi if you just want an easy, cheaper, game-based focus trainer.
Muse S Athena vs Mendi — head-to-head comparison by criterion
Criterion
Winner
Why
Measurement
Muse S Athena
Muse S Athena combines EEG (brain electrical activity) with fNIRS (blood flow) — the first consumer band to do both. Mendi is fNIRS only, which is less granular than EEG.
Sleep tracking
Muse S Athena
The Muse S Athena is a soft band you can sleep in, with EEG-based sleep tracking. Mendi is a focus trainer only — no sleep.
Simplicity & habit
Mendi
Mendi is the easiest device to build a habit with — a single visual bar, productive from session one, no learning curve. Muse offers more, which is also more to learn.
Subscription
Tie
Neither forces a subscription — the Muse S Athena has no mandatory fee, and Mendi is a one-time purchase. A wash.
Price
Mendi
Mendi: $379 list (often discounted). Muse S Athena: $474.99. Mendi is cheaper for pure focus training.
Versatility
Muse S Athena
Muse spans meditation, focus, and sleep with richer data; Mendi does one thing (prefrontal focus training) and does it simply.
Choose Muse S Athena
Choose the Muse S Athena if you want the most complete brain-training headset — EEG plus fNIRS, sleep tracking and real-time neurofeedback in a band you can sleep in.
Choose Mendi
Choose Mendi if you want the simplest, cheapest way to build a daily focus-training habit, with no subscription and no learning curve.
The short version
The Muse S Athena is the most complete headset — EEG plus fNIRS, sleep tracking and neurofeedback; Mendi is a simple, cheaper fNIRS focus trainer with a game-like bar and no learning curve.
When is the Muse S Athena the right pick?
You want the fullest brain-training device — richer measurement, sleep tracking and versatility across meditation, focus and sleep.
When is Mendi the right pick?
You want the simplest, cheapest way to build a daily focus habit, with no subscription and no learning curve.
The Muse S Athena is the more complete device — EEG plus fNIRS, sleep tracking and real-time neurofeedback across meditation, focus and sleep, for $474.99. Mendi is a simpler, cheaper ($379 list, often discounted) fNIRS focus trainer with a game-like bar and no learning curve. Pick Muse for depth and versatility, Mendi for the easiest focus habit.
What’s the difference between EEG and fNIRS here?
EEG measures the brain’s electrical activity; fNIRS measures blood-flow/oxygenation changes. The Muse S Athena uses both (more granular); Mendi uses fNIRS only, which is simpler but less detailed. For richer brain data, Muse; for an easy focus signal, Mendi.
Which is better for sleep?
The Muse S Athena — it’s a soft band you can sleep in with EEG-based sleep tracking. Mendi is a focus trainer only and isn’t made for sleep.