Caffeine Cutoff Calculator – Find Your Last Sip Time for Better Sleep

LastSip^™

Find your perfect caffeine cutoff for
better sleep, every night.

Your Personalized Caffeine
Cutoff Calculator

Beverage: Add Earlier Drink

Bedtime:

Caffeine Sensitivity: Medium

Share Cutoff

LastSip is a free, science-backed caffeine cutoff calculator for better sleep — tailored to your schedule and sensitivity.

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Add Earlier Drink

Beverage:

When did you drink it?

Add Custom Beverage

Beverage Name:

Caffeine (mg):

Your Saved Beverages:

Settings

Sleep Priority

Off On

Lowers your bedtime caffeine threshold to 35mg (from 50mg) for deeper, more protected sleep.

Personalization

Refine your caffeine metabolism based on your body, habits, and lifestyle.

Reset All Preferences

Clear all saved preferences—including your custom drinks and metabolism profile.

v1.2

Personalize Your Caffeine Cutoff

Body Metrics

Height

Weight

Biological Sex / Hormones

Male Female Trans / Intersex

Are you currently...

Pregnant Taking hormonal birth control (e.g., oral contraceptives) Hormonal birth control can double caffeine half-life Neither of these apply

Hormone Therapy Type

Estrogen-based therapy For transition to female/feminizing effects Testosterone-based therapy For transition to male/masculinizing effects

Tip: Tap the ⚙️ gear icon in the corner to revisit these settings.

Lifestyle Factors

Activity Level

Less Active Minimal exercise, mostly sedentary Active Regular exercise 2-4 times per week Very Active Daily exercise or physically demanding job

Typical Bedtime

Do you smoke?

Yes No

Caffeine Sensitivity

How does caffeine affect you?

I barely notice it I can drink coffee late and still sleep well I feel alert but fine I'm cautious with afternoon caffeine I get wired or jittery easily Even morning caffeine might affect me

Fast Caffeine Metabolizer Gene (CYP1A2) Select if genetic testing showed you have the CYP1A2 AA genotype (faster caffeine metabolism)

Do you experience any of these conditions?

Anxiety Insomnia Heart palpitations after caffeine

Caffeine Decay Visualization

Caffeine Curve

Earlier Drinks

Ideal Cutoff

Sleep Threshold

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