Habit & Streak Tracker
Free, private and calculated in your browser
Local habit streak
0 days
Dates use local YYYY-MM-DD keys and remain in this tab until you export them.
About this tool
Habit & Streak Tracker is a privacy-first utility designed to finish a small everyday task without an account, remote API or server-side data store. Inputs are processed in the browser and the visible result is available immediately, including when the calculation itself is performed offline.
The interface keeps the important caveats beside the result. Sensor readings are labeled as estimates, dates and financial projections expose their assumptions, and health or travel information includes a clear reminder to confirm decisions with an appropriate professional or official authority.
How to use
Choose a mode
Open the tool and select the measurement, calculation or study mode that matches your task.
Enter local values
Use the labeled inputs and sample values. Permission-based features request access only after you press their start button.
Review the result
Read the result and its limits. Time-sensitive tools use absolute timestamps so background tabs do not create drift.
Export or reset
Copy or download only when needed, and reset the form when you finish on a shared device.
Use cases
Quick personal workflow
Use it for a one-off measurement, conversion, study session or planning estimate without creating a profile.
Offline and private work
Keep notes, values and local records in the current browser session when connectivity or data sharing is undesirable.
Common mistakes
Mistake:Treating an estimate as a certified measurement or official decision.
Fix:Read the tool disclaimer and use calibrated instruments or official sources when accuracy has legal, medical or safety consequences.
Mistake:Leaving sensitive values open on a shared device.
Fix:Export only the information you need, then clear the form or close the private browser session.
Frequently asked questions
Related guides
Why Sleep Calculators Count in 90-Minute Cycles, Not Hours
The math behind working backward from a wake-up time (or forward from a bedtime) in whole 90-minute sleep cycles, and why waking mid-cycle is what actually causes grogginess.
Naegele's Rule: The 280-Day Math Behind a Due Date
How a due date gets calculated from the first day of your last period, why cycle length and ultrasound dating adjust it, and how the trimester milestones are derived.
References & standards
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