Guides
Plain-English explainers that pair with LK Forge's free tools — from converting time zones across cities to the moon's phases, the sun's seasons, and the weather. Read the one you need, then open the matching tool to see it for yourself.
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Time Zones
How to Convert a Time Between Any Two Cities
The three-step method behind "what's 3 PM UK time in Dubai?" — with worked examples and how to find a meeting slot that suits both sides.
Read guideUTC and GMT Explained
What the global reference clock is, how offsets like UTC+5:30 work, why IANA names beat abbreviations, and how to convert your local time to UTC.
Read guideWhy Time Differences Change: Daylight Saving
What DST is, which regions use it and when, why the gap between two cities isn't always fixed, and how to keep recurring meetings on time.
Read guideRelated tool: Time Zone Converter (GMT, BST, EST…)
Moon
Moon Phases Explained
The eight phases of the moon, why they happen, and how to tell waxing from waning at a glance.
Read guideWhat Is a Blue Moon (and a Supermoon)?
The two meanings of "blue moon", what makes a supermoon, and why neither is actually blue or huge.
Read guideFull Moon Names: Strawberry, Harvest & More
What each month's full moon is called and why — Wolf, Strawberry, Harvest — plus Blue Moons and Supermoons.
Read guideWhy Do Tides Follow the Moon?
How the moon (and sun) pull the oceans into two bulges, and why you get two high tides a day.
Read guideSun & Seasons
Stargazing
Weather
Weather Alerts
Watch vs Warning vs Advisory
What a weather watch, warning, advisory and emergency each mean — and exactly what to do when the NWS issues one.
Read guideWhat Is a Winter Storm Warning?
How a Winter Storm Warning differs from a Watch and an Advisory, what triggers one, and what to do.
Read guideWhat Is an Extreme Heat Warning?
Extreme Heat Warning vs Watch vs Heat Advisory, why it follows the heat index, and how to stay safe.
Read guideWhat Is a Red Flag Warning?
The fire-weather alert explained — the conditions that trigger it and what you should and shouldn't do.
Read guideMeasurement
Metric vs Imperial: What's the Difference?
How the two measurement systems work, who uses which, why the US never switched, and the exact factors worth memorising.
Read guideUnit Conversion Chart
Quick-reference tables for length, weight, volume, temperature, area and speed — metric to imperial and back, exact factors marked.
Read guideScientific Notation
Multiplying Scientific Notation
The one rule — multiply the coefficients, add the exponents — with worked examples, negative exponents, and the normalization step everyone forgets.
Read guideDividing Scientific Notation
Divide the coefficients, subtract the exponents — top minus bottom — plus the opposite-direction normalization and the order mistake to avoid.
Read guideAdding & Subtracting Scientific Notation
Why the exponents must match before you can add, how to line two numbers up on the same power of ten, and what cancellation does to the answer.
Read guideFiles & Formats
How to Change a File Format
Why renaming the extension doesn't convert anything, the three ways to actually convert a file, and the fastest route for HEIC, WebP, PNG, JPG and PDF.
Read guideHow to Convert a Picture to PDF on iPhone
Four free ways, no app needed — the Files app's Create PDF, the hidden print-to-PDF trick, Notes scanning for paper documents, and a browser converter that merges photos into one PDF.
Read guidePages to PDF: Convert an Apple Pages Document
Export from Pages on Mac or iPhone in seconds — and the free iCloud route plus the zip-preview fallback for a .pages file on Windows.
Read guideWidgets
Spin the Wheel Widget for Your Website
Add a free spin-the-wheel widget — a random picker wheel — to any site with one line of code: copy the iframe, paste it in, and preload your own options.
Read guideWorld Clock Widget for Your Website
Add a free live multi-city world clock widget — set your cities with ?cities=, match your theme with ?theme=dark, one line of code.
Read guideEarthquake Map Widget for Your Website
Add a free live earthquake map to any site with one line of code — pin a place with ?place=, preset the ?mag and ?period filters, and match your theme with ?theme=dark.
Read guideHow to Add a Word Unscrambler to Your Website
Embed a free full word unscrambler on any site with one line of code — copy the iframe and optionally preload letters with ?q=.
Read guideHow to Add a Word Search Solver to Your Website
Embed a free word search solver on any site with one line of code — visitors paste a grid and word list and every hidden word is highlighted.
Read guideHow to Add a 2048 Game to Your Website
Embed a free, playable 2048 game — including its built-in AI Hint and Auto-Play solver — on any site with one line of code.
Read guideHow to Add a Reaction Time Test to Your Website
Embed a free reaction time test on any site with one line of code — visitors click when the screen turns green and get their reflex time in milliseconds.
Read guideHow to Add a Gamepad Tester to Your Website
Embed a free gamepad tester on any site with one line of code — visitors connect a controller and see every button, trigger and analog stick respond live.
Read guideHow to Add a Mouse Test to Your Website
Embed a free mouse test on any site with one line of code — check every button, the scroll wheel, double-click faults and mouse polling rate.
Read guideHow to Add a Polygon Area Calculator to Your Website
Embed a free polygon area calculator on any site with one line of code — area from coordinates (shoelace), a triangle’s three sides (Heron), or a regular polygon, with a labelled diagram and steps.
Read guideHow to Add a Simple Pendulum Simulator to Your Website
Embed a free simple pendulum simulator on any site with one line of code — visitors watch a bob swing and trace its arc, drag to set the angle, and compare the measured period with the ideal T = 2π√(L/g).
Read guideHow to Add a Wind Turbine Energy Lab to Your Website
Embed a free wind turbine energy lab on any site with one line of code — set wind speed and rotor size to watch power and the Betz limit.
Read guideHow to Add a Solar Panel Energy Lab to Your Website
Embed a free solar panel energy lab on any site with one line of code — set tilt, latitude and day to watch output and the Shockley-Queisser cap.
Read guideHow to Add a Nuclear Energy Lab to Your Website
Embed a free nuclear energy lab on any site with one line of code — set thermal power and temperatures to watch the Carnot limit and decay heat.
Read guideHow to Add a Geothermal Energy Lab to Your Website
Embed a free geothermal energy lab on any site with one line of code — set brine flow and reinjection to watch net power and reservoir drawdown.
Read guideHow to Add a Battery Storage Lab to Your Website
Embed a free battery storage lab on any website with one line of code. Charge, discharge and watch round-trip efficiency and capacity fade live.
Read guideHow to Add a Pumped Hydro Storage Lab to Your Website
Embed a free pumped hydro storage lab on any website with one line of code. Pump water uphill, generate, and see round-trip efficiency vs flow.
Read guideHow to Add a Flywheel Energy Storage Lab to Your Website
Embed a free flywheel energy storage lab on any website with one line of code. Spin up, draw down and watch standby loss drain the store.
Read guideHow to Add a Hydrogen Energy Storage Lab to Your Website
Embed a free hydrogen energy storage lab on any website with one line of code. Store power as hydrogen and see the low round-trip efficiency.
Read guideHow to Add a Rocket Launch Lab to Your Website
Embed a free rocket launch lab on any website with one line of code. Tune Isp, mass and thrust-to-weight and watch the delta-v ceiling appear.
Read guideHow to Add a Jet Engine Lab to Your Website
Embed a free jet engine lab on any website with one line of code. Tune bypass, OPR and speed and watch thermal and propulsive efficiency.
Read guideHow to Add an Ion Thruster Lab to Your Website
Embed a free ion thruster lab on any website with one line of code. Tune beam voltage and current and explore the Isp–thrust tradeoff.
Read guideHow to Add a Propeller Lab to Your Website
Embed a free propeller lab on any website with one line of code. Tune diameter, RPM and power and explore the actuator-disk efficiency limit.
Read guideHow to Add a Prism Light Dispersion Simulator to Your Website
Embed a free prism light dispersion simulator on any site with one line of code. Split white light into a spectrum and read the deviation live.
Read guideHow to Add a Beer's Law Calculator to Your Website
Embed a free Beer's Law calculator on any site with one line of code. Vary concentration, path length and ε and watch A = εbc bend.
Read guideHow to Add a Calibration Methods Lab to Your Website
Embed a free calibration-methods lab on any site with one line of code. Compare external standard vs standard addition under matrix effects.
Read guideHow to Add a Photometric Error Lab to Your Website
Embed a free photometric error lab on any site with one line of code. See how detector, shot and flicker noise set the best absorbance range.
Read guideHow to Add a Transmission Fitting Lab to Your Website
Embed a free transmission-fitting (TFit) lab on any site with one line of code. See why log(I₀/I) bends and how fitting stays linear.
Read guideHow to Add a Photoelectric Effect Simulator to Your Website
Embed a free photoelectric effect simulator on any site with one line of code — visitors shine light on a metal, eject electrons above a threshold frequency, and measure their energy with a retarding stopping voltage.
Read guideHow to Add a Free Body Diagram Maker to Your Website
Embed a free body diagram maker on any site with one line of code — visitors load a scenario or add their own force arrows, drag to resize, and read the net force, equilibrium and acceleration.
Read guideHow to Add a Bohr Model Simulator to Your Website
Embed a free Bohr model of hydrogen on any site with one line of code — visitors move an electron between energy levels, emit photons, and build the Balmer emission spectrum line by line.
Read guideHow to Add an Ideal Gas Simulator to Your Website
Embed a free ideal gas simulator on any site with one line of code — visitors change the particles, temperature and volume of a gas in a box and watch PV/NT stay constant.
Read guideHow to Add a Doppler Effect Simulator to Your Website
Embed a free Doppler effect simulator on any site with one line of code — visitors move a source and watch its wavefronts bunch ahead and stretch behind, with the pitch shift shown.
Read guideHow to Add a Refraction Simulator to Your Website
Embed a free refraction and Snell's law simulator on any site with one line of code — visitors bend a ray across a boundary, change the media, and find total internal reflection.
Read guideHow to Add a Geometric Optics Ray Diagram Simulator to Your Website
Embed a free ray diagram simulator for lenses and mirrors on any site with one line of code — visitors drag the object and read the image distance, magnification and type.
Read guideHow to Add a States of Matter Simulator to Your Website
Embed a free states of matter simulation on any site with one line of code — visitors add heat to melt a solid and boil a liquid into a gas, with live temperature and phase.
Read guideHow to Add an Electromagnetic Induction Simulator to Your Website
Embed a free electromagnetic induction simulator on any site with one line of code — visitors move a magnet through a coil and watch Faraday's law induce a current.
Read guideHow to Add a Radioactive Decay Simulator to Your Website
Embed a free radioactive decay and half-life simulator on any site with one line of code — visitors watch nuclei decay at random and trace the exponential half-life curve.
Read guideHow to Add a Quantum Tunneling Simulator to Your Website
Embed a free quantum tunneling simulator on any site with one line of code — visitors fire a particle at a barrier and read the exact transmission probability.
Read guideHow to Add a Carnot Cycle Simulator to Your Website
Embed a free Carnot cycle simulator on any site with one line of code — visitors trace a heat engine on a PV diagram and read the efficiency η = 1 − Tc/Th.
Read guideHow to Add a Buoyancy Simulator to Your Website
Embed a free buoyancy and Archimedes simulator on any site with one line of code — visitors drop a block into a fluid and watch it float or sink by density.
Read guideHow to Add a 4-Stroke Engine Simulator to Your Website
Embed a free 4-stroke engine simulator on any site with one line of code — visitors watch the piston cycle through the four strokes beside the Otto-cycle diagram.
Read guideHow to Add a Centripetal Force Simulator to Your Website
Embed a free centripetal force and circular motion simulator on any site with one line of code — students set mass, radius and speed and read F = mv²/r live.
Read guideHow to Add a Torque Simulator to Your Website
Embed a free torque and beam-balance simulator on any site with one line of code — students place masses on a lever and see the moment τ = m·g·d live.
Read guideHow to Add a Hooke's Law Simulator to Your Website
Embed a free Hooke's law simulator on any site with one line of code — students hang masses on a spring and read the spring constant off a live F–x graph.
Read guideHow to Add a Coulomb's Law Simulator to Your Website
Embed a free Coulomb's law simulator on any site with one line of code — students set two charges and a separation and see F = kq₁q₂/r² attract or repel.
Read guideHow to Add a Circuit Simulator to Your Website
Embed a free Ohm's law circuit simulator on any site with one line of code — students wire resistors in series or parallel and read current, voltage and power.
Read guideHow to Add an RC / RL Circuit Simulator to Your Website
Embed a free RC and RL circuit simulator on any site with one line of code — students watch a capacitor or inductor charge and discharge with the time constant τ.
Read guideHow to Add a Logic Gate Simulator to Your Website
Embed a free logic gate simulator on any site with one line of code — students toggle inputs through AND, OR, NOT, XOR and more, with live truth tables.
Read guideHow to Add an Inclined Plane Simulator to Your Website
Embed a free inclined plane simulator on any site with one line of code — visitors put a block on a ramp, change the angle and friction, and watch it hold or slide.
Read guideHow to Add a Black Hole Simulator to Your Website
Embed a free black hole simulator on any site with one line of code — visitors watch an accretion disk orbit an event horizon and read the Schwarzschild radius.
Read guideHow to Add a Double Pendulum Simulator to Your Website
Embed a free double pendulum simulator on any site with one line of code — visitors set two coupled pendulums swinging into deterministic chaos and launch a "chaos twin" to watch the paths diverge.
Read guideHow to Add Simple Harmonic Motion to Your Website
Embed a free simple harmonic motion simulator on any site with one line of code — a mass on a spring or a pendulum drawing its own sine wave as it trades energy back and forth.
Read guideHow to Add a Gravity Simulator to Your Website
Embed a free gravity simulator on any site with one line of code — load the Sun–Earth–Moon, a binary star or the chaotic three-body problem and fling in new planets.
Read guideHow to Add a Wave on a String to Your Website
Embed a free wave-on-a-string simulator on any site with one line of code — send a pulse that reflects, or drive the end into a standing wave.
Read guideHow to Add the Double-Slit Experiment to Your Website
Embed a free double-slit experiment on any site with one line of code — fire waves or single photons through two slits and watch interference fringes build up dot by dot.
Read guideHow to Add a Lorenz Attractor to Your Website
Embed a free Lorenz attractor in rotatable 3D on any site with one line of code — the butterfly of chaos theory, with a twin that shows sensitive dependence.
Read guideHow to Add a Bifurcation Diagram to Your Website
Embed a free logistic-map bifurcation diagram on any site with one line of code — the period-doubling road to chaos, with click-to-inspect and fractal zoom.
Read guideHow to Add a Reaction-Diffusion Simulator to Your Website
Embed a free reaction-diffusion lab on any site with one line of code — Gray-Scott Turing patterns of spots, stripes, mazes and coral that you paint yourself.
Read guideHow to Add Conway's Game of Life to Your Website
Embed Conway's Game of Life on any site with one line of code — draw cells, drop in gliders, guns and oscillators, and watch patterns evolve from four rules.
Read guideHow to Add a Fluid Simulation to Your Website
Embed a free real-time fluid simulation on any site with one line of code — stir dye and velocity with your mouse and watch vortices form.
Read guideHow to Add a Charged Particle Simulator to Your Website
Embed a free charged-particle lab on any site with one line of code — cyclotron circles, E×B drift, and a dipole mode where particles spiral to the poles.
Read guideHow to Add an Aurora Simulator to Your Website
Embed a free aurora simulator on any site with one line of code — solar-wind particles spiral along Earth’s field and light the northern lights at both poles.
Read guideHow to Add a Particle Collider to Your Website
Embed a free particle collider on any site with one line of code — smash electron and positron beams and slide the energy to 91 GeV to light up a Z⁰ boson.
Read guideHow to Add a Projectile Motion Simulator to Your Website
Embed a free projectile motion simulator on any site with one line of code — set the angle, speed and gravity, toggle air resistance, and read range, height and time.
Read guideHow to Add a Collision Simulator to Your Website
Embed a free collision simulator on any site with one line of code — set masses, speeds and elasticity and watch momentum stay conserved while energy is lost.
Read guideHow to Add an Electric Field Simulator to Your Website
Embed a free electric field simulator on any site with one line of code — drop point charges and watch the field appear as field lines or vectors.
Read guideGame Analysis
How to Analyze a Chess Position
Use the free built-in chess analyzer to evaluate any position — best move, an evaluation bar for who’s winning, the likely line, and mate detection, all in your browser.
Read guideHow to Analyze an Othello Position
Use the free built-in Othello (Reversi) analyzer to evaluate any position — best move, an evaluation bar for whether Black or White is ahead, and search depth, all in your browser.
Read guideHow to Analyze a Checkers Position
Use the free built-in checkers (draughts) analyzer to evaluate any position — best move, an evaluation bar for whether Red or Black is ahead, and search depth, all in your browser.
Read guideHow to Analyze a Mancala Position
Use the free built-in Mancala (Kalah) analyzer to evaluate any position — best pit to play, an evaluation bar for whether you or the computer is ahead, and search depth, all in your browser.
Read guideHow to Analyze a Backgammon Position
Use the free built-in backgammon analyzer to read any position — the pip count for both sides, who leads the race, and an evaluation bar for whether White or Black is favored, all in your browser.
Read guideHow to Use the 2048 Solver
Use the free built-in 2048 AI solver — get the best next move with Hint, watch Auto-Play run the corner-snake strategy, or hand it your own board to solve, all in your browser.
Read guideHow to Use the Sudoku Solver and Hint Engine
Use the free built-in Sudoku AI hint engine — get the next forced move with the technique named, auto-fill candidates, and play graded puzzles that always have one solution.
Read guideHow to Use the Minesweeper Solver
Use the free built-in Minesweeper solver — get a guaranteed-safe hint, read each cell’s exact mine probability, and play a No-Guess mode with boards proven solvable, all in your browser.
Read guide