SlothLab Toolsšæ Life
Everyday calculators for daily life decisions
Life's daily decisions add up. Our lifestyle calculators help you optimize everyday choices, from knowing when to stop drinking coffee for better sleep to calculating the right tip when traveling abroad. The sleep cycle calculator uses the science of 90-minute sleep stages to recommend optimal bedtimes, while the timezone converter simplifies scheduling across global teams. These are practical tools built for real situations ā travel, remote work, health optimization, and daily planning.
Why This Matters
Small daily habits compound into significant health and productivity outcomes. Research shows that caffeine consumed even 6 hours before bed can reduce total sleep by over an hour. Proper sleep timing aligned with natural cycles can improve how rested you feel without sleeping more. And for the millions of people who work remotely across time zones, quick timezone conversion prevents scheduling mistakes that waste everyone's time.
Global Tip Guide
Know how much to tip anywhere in the world.
Caffeine Cutoff Calculator
Find the latest time you can have caffeine and still sleep well.
Sleep Cycle Calculator
Find the best time to sleep or wake up based on 90-minute sleep cycles.
Timezone Converter
Convert time between world cities. Compare multiple timezones at once.
Guides
The Science of Caffeine and Sleep: How Coffee Affects Your Rest
Discover how caffeine works in your body, its half-life, how it disrupts sleep architecture, and the science behind optimal caffeine cutoff times.
The Science of Sleep Optimization: Cycles, Caffeine, and Practical Strategies for Better Rest
Learn how sleep cycles work, optimize your bedtime with the 90-minute rule, manage caffeine timing, and implement evidence-based strategies for better sleep quality.
Mastering Timezone Management for Remote Work and Global Collaboration
Learn practical strategies for working across timezones, scheduling international meetings, managing distributed teams, and maintaining work-life balance in remote work.