About Lunarly
Lunarly is a free daily companion built around three simple tools: a moon phase calculator, a days alive counter, and a personalised affirmation generator.
We built it with one belief: that small moments of reflection — pausing to notice the moon, to count the days you've lived, to say something kind to yourself — compound into a meaningfully different way of moving through life.
Everything runs in your browser. We do not store your birthdate on a server. We do not sell your data. The email list is the only thing we collect, and only if you choose to join it.
How the moon phase calculator works
We use a well-tested astronomical algorithm (via the SunCalc library) to compute the moon's illumination fraction and phase angle for any given date. The result is accurate to within a fraction of a degree for dates within a few centuries of today.
How the days alive calculator works
Simple date arithmetic: the number of milliseconds between your birthdate and today, divided by the number of milliseconds in a day. Heartbeats and breaths are estimated using average resting rates (70 bpm and 15 breaths per minute respectively).