Try the new Cosinor.Online Public Beta

Explore the redesigned interface and new analysis features. The beta is still being tested, so you may encounter errors and its stored data may later be removed.

Try the Public Beta
Discover powerful new features for your analysis, developed based on years of user feedback
Available for All Users:
  • Polar Plot: Analyze the phase and amplitude of your rhythms.
  • Lomb-Scargle Periodogram: Detect dominant periods in your data.
  • Goodness of Fit Stats: Evaluate your model with R² and Correlation (R).
Exclusive Features for Registered Users:
  • Multi-Dataset Comparison: Visualize multiple Cosinor fits in a single plot.
  • Data Export to CSV: Download your results for further analysis and publications.
  • Saved Results History: Securely access and manage all your past analyses anytime.
New Features Preview

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Circadian Rhythms and Time-Dependent Biological Processes

Biological rhythms — especially circadian (~24 h) and ultradian cycles — reflect how internal and environmental factors shape physiological processes over time. Cosinor.Online is a free, browser-based tool that helps researchers analyse such time-distributed data using the classic cosinor method: Y = M + A × cos(2π × (t – φ) / T). No installation or coding is required.

More about Cosinor.Online → Manual →
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137.5
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12.4