Solar Light Sun Exposure Plotter – Online Daily Direct Sun Check
Select your latitude and day of year to see sun path and identify spots with the most direct sunlight for solar garden lights. Simple visual tool.
UD5 Toolkit
Visualize totality — watch the Moon's shadow sweep across the Sun
Select your latitude and day of year to see sun path and identify spots with the most direct sunlight for solar garden lights. Simple visual tool.
Type a UPC or EAN number and see how a laser scanner would identify it, plus check digit validation.
Calculate absolute error, relative error, and percent error between experimental and theoretical values. For science students. Instant local math.
Ask a yes/no question and click to reveal a classic Magic 8-Ball response. Animated shake effect. Nostalgic fun, pure local randomness.
Set up resources and processes and run the Banker's algorithm to check for safe states. Classic OS deadlock avoidance demo.
Simulate memory page reference strings with FIFO, LRU, and Optimal algorithms. See page fault count. OS concept demo.
Adjust page characteristics (image size, server delay, layout shift) and see the simulated Core Web Vitals scores. Understand what impacts performance.
Open many parallel WebSocket connections and send messages. Test your server's concurrency. All from your browser.
Click for a fascinating, verified science fact. From biology to physics. Expand your knowledge. Lightweight and static.
Keep track of a tennis match: points, games, sets, and deuce. Supports tiebreak. Great for friendly matches. Local.
Upload any image and view it as a person with deuteranopia, protanopia, or tritanopia would. Promote inclusive design.
Roll any number of dice thousands of times and see a live bar chart of the sum distribution. Great for game designers.
Select functional groups to see an approximate IR absorption spectrum. Learn spectroscopy visually. All local.
Simulate random mouse moves, clicks, or keystrokes to test idle‑timeout logic. Stops when you move the mouse. Dev test.
View the NASA Astronomy Picture of the Day (APOD) directly in your browser. Read the explanation. No API key needed.
Type any CSS selector with :hover/:active/:focus and see the styles applied live. Perfect for debugging interaction states.
Set a cron expression and see a calendar of the next 1,000 execution times. Never miss a schedule again.
Adjust ISO, aperture, and shutter speed sliders and see how it affects the exposure of a sample scene. Learn photography basics.
Convert a Gregorian calendar date to its Julian Day Number and vice versa. Used in astronomy and mainframe computing.
Select telescope and eyepiece parameters to see the field of view circle on a simulated night sky image.
Watch the planets orbit the Sun in a top‑down 2D view. Adjust speed and zoom. Distances not realistic; beautiful model.
Generate a realistic‑sounding exoplanet designation (e.g., Kepler‑442b) and a sci‑fi planet description. For worldbuilding.
Fold a virtual square paper step by step with crease lines and visual previews. Practice origami basics without wasting real paper. All canvas‑based.
Count significant digits in a number and round to a specific number of sig figs. Perfect for chemistry and physics labs.
Zoom through sizes from the Planck length to the observable universe. Educational and awe‑inspiring visualization.
Enter a URL and get a rough client-side performance simulation: request count, DOM size, and potential speed tips. No real Lighthouse.
Control a lunar module and try to land softly on the moon. Manage fuel and thrust. Classic arcade physics. Canvas.
Click on a constellation to see its star pattern and read the Greek mythology behind it. Beautiful CSS illustration.
Simulate how images and UI elements appear to users with various types of color blindness. Upload or paste image URL. Promote inclusive design.
Flip a virtual coin to make a decision or settle a dispute. Realistic animation and fair random outcome. Simple, fast, and always available.