☀️ 100% Free & Private

Circadian Fasting &
Metabolic Rhythm

Track your intermittent fasts with elegance, biological precision, and zero clutter. Understand what happens in your body at every hour.

📲 Download on the App Store
Solstice Fasting Timer
Goal Reached Glow
Metabolic Fasting Stages
Calendar Streak Heatmap
24 Hour Protocol Dial

Built for Mindfulness & Discipline

Everything you need to master your fasting window, and nothing you don't.

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5 Metabolic Stages

Real-time biological timeline tracking when your body reaches Blood Sugar Reset, Glycogen Depletion, Fat Burning, Autophagy, and Deep Ketosis.

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100% On-Device & Private

No accounts, no sign-in, and zero analytics tracking. Your health and fasting records stay strictly on your device.

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Adaptive Dial Wheel

Choose standard presets (16:8, 18:6, 20:4, OMAD) or adjust your target with an interactive 24-hour dial.

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Streak & Calendar Heatmap

Glanceable monthly heatmap to celebrate consecutive daily milestones and build permanent wellness habits.

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OLED Dark Theme

Engineered with deep midnight tones and radiant solar gradients that feel effortless to check morning and night.

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No Paywalls or Subscriptions

Enjoy a clean, undisturbed fasting experience without popup advertisements or locked feature walls.

The Science of Your Fast

Solstice calculates your body's biological transitions in real time.

0 – 4 Hours

🩸 Blood Sugar Reset

Insulin levels fall, digestion completes, and blood glucose stabilizes.

4 – 12 Hours

⚡️ Glycogen Depletion

Liver stores are consumed as energy sources shift toward fat stores.

12 – 18 Hours

🔥 Fat Burning & Ketosis

Fatty acids are broken down into ketones for clean mental and physical fuel.

18 – 24 Hours

🧬 Autophagy & Renewal

Cellular cleanup initiates, recycling damaged proteins and organelles.

24+ Hours

🧠 Deep Ketosis & HGH

Growth hormone surges and systemic inflammation markers drop.

Need Help or Have an Idea?

We build Solstice for the community. Let us know how we can make your fasting journey even better.

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