Most water tracking apps tell you one thing: how many milliliters you drank today compared to your goal. That's useful — but it's incomplete. Did you drink consistently throughout the day, or did you chug everything at 10pm? Did you regularly hit your goal all week, or just today? Did you wildly over-drink?
Suu's hydration score captures all of this in a single 0-100 number — a composite performance rating that tells you not just how much you drank, but how well you hydrated.
The Four Components of Your Hydration Score
| Component | Weight | What It Measures |
|---|---|---|
| Completion | 50% | Average daily goal achievement rate over the period |
| Regularity | 20% | Consistency day-to-day (penalizes big swings) |
| Timing | 20% | How well intake is spread across the day |
| Over-intake | 10% | Penalty for chronically drinking far above goal |
1. Completion (50% weight) — The Most Important Factor
This is the average of your daily goal completion rates over the measured period. If your daily goal is 2,500ml and you drank 2,250ml, your completion for that day is 90%. Your completion score is the average across all days in the period.
Example: Mon 90%, Tue 75%, Wed 100%, Thu 80%, Fri 65%, Sat 95%, Sun 85% → average 84.3% completion → contributes 84.3 × 0.50 = 42.15 points
2. Regularity (20% weight) — Consistency Is Key
This measures how stable your daily intake is. The formula: 100 − (daily_ml_standard_deviation × 0.6). A large standard deviation — meaning some days you drink a lot and other days very little — reduces this score. Steady, predictable hydration is rewarded.
Why does this matter? Sporadic hydration (1,000ml Monday, 3,500ml Tuesday) puts stress on your body just like sporadic eating. Your kidneys prefer a consistent water supply to process efficiently.
3. Timing (20% weight) — Spread It Through the Day
Your score is higher when you drink across many different hours of the day. Formula: 50 + (unique_hours_logged / 10 × 50). Logging across 10+ different hours gives maximum timing score. Drinking all your water in a 2-hour window gives a low timing score.
Science backs this up: small, frequent sips throughout the day maintain blood plasma volume more effectively than large infrequent gulps. Your body absorbs water better in smaller doses.
4. Over-Intake Penalty (10% weight) — Don't Overdo It
Drinking significantly more than your goal every day isn't optimal — it can lead to electrolyte dilution and other issues. This component scores: 100 − (excess_ml / (goal × days) × 50). Consistently drinking 2x your goal would reduce this component. Moderate over-drinking (10-20% above goal) has no meaningful impact.
💡 Note: The over-intake penalty only applies to consistent large excess. Occasionally drinking more than your goal (like after a hard workout) doesn't significantly affect your score.
What Each Score Range Means
85–100 (Excellent): You're consistently meeting your goal, drinking throughout the day, and doing it every day. This is the hydration equivalent of a well-balanced diet — optimal for cognition, metabolism, and physical performance.
70–84 (Good): You're doing well but there's room for improvement — probably in timing (drinking too much at once) or regularity (skipping some days). Small adjustments will get you to Excellent.
40–69 (Improving): You're tracking and making progress. Common pattern here: hitting goal on weekdays, forgetting on weekends. Focus on consistency.
0–39 (Needs Work): Either completing less than 50% of goal most days, or irregular patterns. The most important fix is hitting your daily goal — even reaching 80% consistently will rapidly move this score up.
Your Hydration Persona
Alongside your score, Suu assigns you a hydration persona based on your behavioral patterns:
- Morning Opener: You drink significantly more in the morning (6-10am) than in the evening. Morning hydration is great — just don't forget the afternoon.
- Evening-Focused: Most of your intake happens after 6pm. This often means forgetting to drink during the day and cramming at night — which hurts your timing score.
- Frequent Sipper: 6+ distinct logging events per day. Ideal pattern. Small, frequent intake maximizes absorption and keeps energy stable.
- Balanced Drinker: Spread consistently across the day without a single dominant time window. Second best to Frequent Sipper.
How to Improve Your Hydration Score
Set Time-Based Reminders
Schedule Suu notifications every 2-3 hours to encourage consistent logging throughout the day. This directly boosts your Timing score.
Use Widgets & Apple Watch
Suu's lock screen widget and Apple Watch app make logging faster, reducing friction. Less friction = more consistent logging.
Focus on the 80% Rule
Hitting 80% of your goal consistently scores better than hitting 100% some days and 40% others. Completion drives 50% of your score.
Don't Skip Weekends
The biggest drop in most users' Regularity score comes from weekend lapses. Even a minimum of 1,500ml on off days keeps regularity high.
Where to Find Your Score in the App
- Open Suu on your iPhone or Android device.
- Tap the Statistics tab (chart icon).
- Select a time period: weekly, monthly, or custom range.
- Your hydration score appears at the top of the report, along with your persona and coaching tips.
- Tap the score to see a breakdown of all four components.
- To export as PDF, tap the share icon — your score is included in the report.
Check Your Hydration Score Today
Suu is the only water tracking app with a real hydration performance score — free on iOS and Android.
The Bottom Line
A hydration score is only useful if it tells you something actionable. Suu's score breaks down your performance into four clear components, so you know exactly which behavior to change. Whether it's drinking earlier in the day, maintaining consistency on weekends, or simply hitting 80% of your goal — the score points you in the right direction.
No other water tracking app — not WaterMinder, not Hydro Coach — offers this level of analytical detail. It's one of the reasons Suu is the most data-driven hydration app available in 2026.