# Biorhythm Curve Plotter Plot the classic 23-day physical, 28-day emotional, and 33-day intellectual biorhythm sine curves around any target date. See today's cycle states, mark zero-crossing "critical days", and read a daily value table with a combined total — enter your date of birth and a target date. > Canonical page: https://elysiatools.com/en/tools/biorhythm-curve-plotter - **Category:** Health - **Keywords:** biorhythm, biorythm, physical cycle, emotional cycle, intellectual cycle, critical day, sine wave, 23 28 33, rhythm chart, birth date, cycles, wellness ## Overview A biorhythm chart generator based on the classical three-cycle hypothesis: 1. **Enter your date of birth** and a target date (defaults to today). 2. **The tool computes** the three sine waves for physical (23d), emotional (28d), and intellectual (33d) cycles. 3. **SVG chart** — clean plot of all three curves around the target date with grid and date ticks. 4. **Critical days** — zero-crossings marked and listed. 5. **Daily table** — every day's values plus a combined total. ⚠️ Biorhythm theory is a historical curiosity and is **not scientifically validated**. ## Inputs - **Date of birth** (date) - **Target date (today by default)** (date) - **Chart range** (select) - **Days to plot** (number): Total days shown. In "around" mode this is split evenly before/after the target date. ## When to use - When you want to visualize the classic three-cycle biorhythm curves around a specific target date or event. - When you need to identify zero-crossing critical days where physical, emotional, or intellectual cycles transition between positive and negative phases. - When you want to generate a clean SVG chart and daily value table of biorhythm data for personal reflection or historical curiosity. ## How it works - Input your date of birth and select a target date to center the calculation. - Choose the chart range mode, either centered around the target date or spanning from birth, and set the number of days to plot. - The tool calculates the three sine waves using the classic 23-day physical, 28-day emotional, and 33-day intellectual periods. - It renders an interactive SVG chart highlighting the target date, marks zero-crossing critical days, and outputs a daily value table with combined totals. ## Use cases - Plotting a 30-day biorhythm chart around an upcoming exam or job interview to check the intellectual and emotional cycle phases. - Identifying upcoming critical days where multiple cycles cross the zero threshold simultaneously. - Generating a historical biorhythm chart starting from birth to analyze cycle patterns over a longer timeframe. ## Frequently asked questions ### What are the three cycles calculated by the tool? The tool calculates the 23-day physical cycle, the 28-day emotional cycle, and the 33-day intellectual cycle. ### What is a critical day in biorhythms? A critical day occurs when a cycle curve crosses the zero line, transitioning between positive and negative phases, which theoretically represents instability. ### Is biorhythm theory scientifically proven? No, biorhythm theory is a historical hypothesis from the late 19th century and has no scientific validation. ### Can I change the number of days displayed on the chart? Yes, you can adjust the span of days to plot anywhere from 6 to 120 days using the span days option. ### What does the combined total in the daily table represent? It is the sum of the physical, emotional, and intellectual cycle values for that day, ranging from -300 to +300. ## Related tools - [Doppler Effect Calculator (Frequency Shift)](https://elysiatools.com/en/tools/doppler-effect-calculator): Compute observed frequency and frequency shift for a moving source and/or observer - [Audio Cutter](https://elysiatools.com/en/tools/audio-cutter): Cut and extract audio clips from audio files with precise time selection - [Video Audio Extract Enhanced](https://elysiatools.com/en/tools/video-audio-extract-enhanced): Extract audio from video files with advanced options - multiple formats, quality settings, and audio enhancement - [Video to WAV Converter](https://elysiatools.com/en/tools/video-to-wav): Extract audio from video and convert to WAV (PCM) with optional resampling and channel selection - [Frequency ⇄ Wavelength Converter (Hz/kHz/MHz/GHz/THz ⇄ m/cm/mm/nm)](https://elysiatools.com/en/tools/frequency-wavelength): Convert between frequency and wavelength with selectable medium; results in all common frequency and length units - [Microscope Scale Bar Calibrator](https://elysiatools.com/en/tools/microscope-scale-bar-calibrator): Calculate microscope object scale, field of view, diffraction limits, Nyquist sampling, and download a transparent SVG scale bar. - [Rating Star Chart](https://elysiatools.com/en/tools/rating-star-chart): Create beautiful star rating visualizations for products, services, and user feedback analysis with interactive animations - [Wavelength Calculator (λ = v/f, period, wave number, angular frequency)](https://elysiatools.com/en/tools/wavelength-calculator): Solve wavelength, frequency, or wave speed from v=f·λ, with derived period, angular frequency, wave number, and photon energy ## Samples - [Copyright-Free MP3 Audio Samples](https://elysiatools.com/en/samples/mp3-samples): Collection of royalty-free audio samples for testing and development purposes including nature sounds, meditation music, and ambient audio - [Copyright-Free WAV Audio Samples](https://elysiatools.com/en/samples/wav-samples): Uncompressed PCM WAV audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music - [Copyright-Free Raw PCM Audio Samples](https://elysiatools.com/en/samples/pcm-samples): Raw PCM s16le audio samples featuring nature ambience and relaxing music for waveform, playback, and conversion workflows - [Speech Learning & Safety Audio Samples](https://elysiatools.com/en/samples/audio-learning-safety-samples): Deterministic synthetic WAV inputs for pronunciation comparison, dictation preflight, alert degradation, and voice privacy tools. ## Related content - [Text Extraction Tools](https://elysiatools.com/en/hubs/text-extract): Explore 15 tools for extracting links, emails, phone numbers, dates, emojis, HTML attributes, and other structured signals from mixed text. - [Document OCR and Structured Extraction Tools](https://elysiatools.com/en/hubs/document-ocr-extraction): Extract text, Markdown, JSON, tables, captions, and RAG-ready chunks from scanned PDFs and document images with OCR and structure-aware workflows. - [PDF to LLM and RAG Preparation Tools](https://elysiatools.com/en/hubs/pdf-llm-rag-prep): Prepare PDFs for AI workflows by extracting clean text, structured Markdown and JSON, tables, OCR layers, chunk packs, and safety review signals before indexing or prompting. - [Archive Preview, Selective Extraction, and Format Conversion Tools](https://elysiatools.com/en/hubs/archive-preview-selective-extraction-and-conversion): Inspect ZIP, 7Z, TAR, TAR.GZ, and GZIP archives, extract only the files you need, and convert formats in one archive workflow hub.