Engineering 112
Electronics and mechanical calculators, quality control, statistics, developer tools, device checks — and an equipment UPH simulator
Build an equipment frame from a questionnaire, run module, robot, transfer-chamber and cassette flow, and read UPH and bottlenecks
AppsProcessStat · statistics workshopEnter your numbers and get distributions and normality, two-group, paired, one-sample and multi-group comparisons, process capability, control charts and correlation/regression, with the results explained
AppsDOE design-of-experiments builderBuild full and fractional factorial, Plackett–Burman, orthogonal-array, central-composite and Box–Behnken designs with center points, replicates, blocks and random run order, then record Y values and save the plan
AppsGetting started · examples and tutorialsThirteen lessons for people new to statistics, example numbers with step-by-step practice, how to read results, quizzes, 24 glossary terms, an FAQ, manuals and printable workbooks
Research & statistics 15
- Scale Bar Measurement ToolMeasure lengths, areas and angles on SEM and microscope images using the scale bar. Images never leave your device
- Graph Data ExtractorTurn a chart image back into numbers: set the axes, click the points, export the data
- Image Click CounterCount cells, particles or colonies by clicking on a photo, with a tally per category
- Error Propagation & Significant Figures CalculatorPropagate measurement uncertainty through a formula and round the result to the right significant figures
- Molarity & Dilution CalculatorMass needed for a molar solution, and C1V1 = C2V2 dilutions
- Multi-Timer for the LabRun several named timers at once for incubations and protocol steps
- Molar Mass CalculatorType a chemical formula to get its molar mass and percent composition
- Periodic TableAn interactive periodic table: tap an element for its atomic weight, configuration and more
- Physical ConstantsLook up and copy physical and chemical constants such as c, h, k and Avogadro's number
- Statistics CalculatorPaste data to get descriptive statistics, t-tests, ANOVA, correlation and regression, each with a plain-language reading
- Chart MakerPaste data to draw box plots, histograms, scatter plots, Pareto charts and more, then save as an image
- Probability Distribution CalculatorProbabilities and critical values for the normal, t, chi-square and F distributions
- Sample Size CalculatorHow many responses or samples you need for a given confidence level and margin of error
- Chemical Equation BalancerBalance a chemical equation with the smallest whole-number coefficients
- Curve Fitting CalculatorFit a line, polynomial, exponential, logarithmic or power curve to your data and get the equation and R²
Manufacturing & quality 12
- Number GeneratorGenerate random numbers, data with a chosen mean and sigma, or data that hits a target Cpk
- Process Capability Calculator (Cp, Cpk)Paste measurements to get Cp, Cpk, Pp, Ppk, a histogram and expected defect rates
- Control Chart MakerDraw X-bar & R, X-bar & S, I-MR, p, np, c and u charts from your data and flag out-of-control points
- Defect Rate, PPM & Sigma Level ConverterConvert between defect rate, PPM, DPMO, yield, sigma level and Cpk
- OEE CalculatorOverall Equipment Effectiveness from run time, output and defects: availability, performance, quality
- Takt Time CalculatorTakt time from available working time and customer demand
- AQL Sampling TableEnter lot size, inspection level and AQL to get the sample size and accept/reject numbers
- Hardness ConversionConvert between Rockwell (HRC, HRB), Vickers (HV), Brinell (HB), Shore and approximate tensile strength
- Metal Weight CalculatorPick a material and shape (plate, round bar, tube, angle…), enter the dimensions and get the weight
- Fishbone Diagram MakerType the problem and its causes to draw an Ishikawa cause-and-effect diagram
- EOQ Calculator (Economic Order Quantity)The most economical order size, orders per year and reorder point from demand, ordering cost and holding cost
- Gage R&R CalculatorPaste measurement study data to get repeatability, reproducibility, %GRR and ndc
Mechanical & electronics 14
- Resistor Color Code CalculatorPick the bands to read a resistor's value and tolerance, or enter a value to see its bands
- Ohm's Law CalculatorEnter any two of voltage, current, resistance and power to get the other two
- Series & Parallel Resistor CalculatorTotal resistance of resistors in series or parallel, and the best standard pair for a target value
- Voltage Divider CalculatorOutput voltage from two resistors, or the resistor pair that gives the voltage you want
- LED Resistor CalculatorSeries resistor value and wattage for an LED from supply voltage, forward voltage and current
- RC Time Constant & Filter Cutoff CalculatorTime constant, charge time and low-pass or high-pass cutoff frequency from R and C, plus reactance and LC resonance
- Decibel Calculator (dB, dBm, Watts)Convert power and voltage ratios to dB, dBm to watts, and add decibel levels
- Drill Size Chart & Tap Drill ChartNumber, letter, fractional and metric drill sizes in inches and mm, with tap drill sizes for common threads
- Pulley & Belt Length CalculatorSpeed ratio, belt length, centre distance and belt speed from pulley diameters
- Speeds and Feeds CalculatorSpindle RPM from cutting speed and diameter, and feed rate from feed per tooth, for milling, turning and drilling
- Battery Life CalculatorEstimate how long a battery lasts from its capacity and the current your device draws
- 555 Timer CalculatorFrequency, duty cycle and pulse width for astable and monostable 555 timer circuits
- Flow Rate & Pipe Velocity CalculatorFlow from pipe size and velocity, velocity from flow and size, or the diameter you need
- O-Ring Size ChartLook up O-ring sizes by inside diameter and cross-section (AS568, JIS B 2401, ISO 3601)
Developers 16
- JSON Formatter & ValidatorPaste JSON to pretty-print it, validate it and find the error line
- Regex TesterTest a regular expression live: see matches, capture groups and replacements
- Base64 & URL Encoder/DecoderEncode and decode Base64, URL (percent) encoding and HTML entities
- JWT DecoderDecode a JSON Web Token's header and payload. The token is never sent anywhere
- Unix Timestamp ConverterConvert Unix timestamps to dates and back
- UUID & Hash GeneratorGenerate UUIDs and compute MD5 and SHA hashes of text or files
- Color Code ConverterConvert between HEX, RGB, HSL, HSV and CMYK, and check text contrast
- Truth Table GeneratorEnter a logic expression to get its truth table and a simplified form
- Number Base Converter (Binary, Hex, Decimal)Convert between binary, octal, decimal, hexadecimal and any base, with steps and bitwise operations
- IP Subnet Calculator (CIDR)Network address, broadcast address, host range and host count from an IP address and mask
- Chmod CalculatorTick read, write and execute to get the octal (755) and symbolic (rwxr-xr-x) Linux permissions and the command
- Cron Expression Generator & ExplainerExplain a cron expression in plain words, list its next run times, or build one by picking a schedule
- XML Formatter & ValidatorPretty-print or minify XML, find syntax errors and browse it as a tree
- SQL FormatterTurn a one-line SQL query into clean, indented SQL
- YAML Validator & YAML ↔ JSON ConverterCheck YAML for errors and convert between YAML and JSON
- CRC CalculatorCRC-8, CRC-16 and CRC-32 checksums of text or hex bytes, with common presets and custom polynomials
Device tests 6
- Webcam TestCheck that your camera works and see its resolution and frame rate. Nothing is recorded or sent
- Microphone TestSee your mic level live, then record a few seconds and play it back
- Keyboard TestPress keys to light them up on an on-screen keyboard and find dead or stuck keys
- Dead Pixel TestFill the screen with solid colours to spot dead or stuck pixels and backlight bleed
- Speaker Test (Left/Right)Play a tone in the left or right channel to check stereo and connections
- Refresh Rate TestMeasure how many times per second your screen is redrawing (Hz)
Sound & screen 5
- Sound Level MeterSee how loud it is around you through the microphone. Readings are relative, not calibrated decibels
- Screen RecorderRecord your screen, a window or a tab and save the video, with no install. Desktop browsers only
- Voice RecorderRecord from your microphone and save the file. Recordings stay on your device
- TeleprompterScrolls your script at a steady speed for presentations and video recording
- White Screen LightFill the screen with bright white or any colour to use it as a light or tracing pad
Other tools 1
Also on this shelf 43
- Triangle & Angle CalculatorEnter a run and a rise to get the slope length and angle. Solves right, isosceles and general triangles, and arcs
- Equation EditorWrite an equation, preview it, and take it away as an image (PNG, SVG) or LaTeX code
- Image Color Picker & PalettePull the main colours out of a photo as colour codes, and pick the colour of any pixel
- Screen Measuring ToolsUse your screen as a ruler. Calibrate once with a card or coin and measure at real size
- Online ProtractorMeasure an angle with a protractor on your screen, or on top of a photo
- Bubble LevelLay your phone down to see the tilt
- Circle Diameter GaugeHold a round object against the screen, match the circle, and read its diameter, radius, circumference and nearest standard size
- Bolt & Nut Size FinderHold a bolt against the screen to find its size (M5, M6, 1/4-20…), length, and the hex key or wrench that fits
- Pipe & Fitting Size FinderMeasure a pipe's outside diameter and get its nominal size (1/2 in, DN15, 15A…)
- ZIP & UnzipPack files into a ZIP or pull files out of one, without uploading anything
- CSV, JSON & Table ConverterConvert between CSV, pasted spreadsheet tables, JSON and Markdown tables
- Tolerance Stack-Up CalculatorAdd up dimensions and tolerances to get worst-case and statistical (RSS) stack-up
- Bolt Circle Calculator (PCD)X and Y coordinates of each hole from the pitch circle diameter and number of holes
- Limits & Fits Calculator (ISO 286)Enter a basic size and tolerance class (H7, g6…) to get the limits and the type of fit
- Photo StitcherJoin overlapping flat shots — microscope tiles, scrolling screenshots, split scans — into one image
- Table to LaTeX & MarkdownPaste a spreadsheet table and get LaTeX, Markdown or HTML table code
- Text Compare (Diff)Find and highlight the differences between two texts
- Case ConverterConvert text to upper, lower, sentence or title case (APA, MLA, Chicago), camelCase and more
- Markdown PreviewWrite Markdown and see the result side by side; export as HTML
- Unit Converter — Length, Weight & TempConvert inches to cm, lbs to kg, °F to °C, psi to bar and GB to GiB across 19 categories, with every unit shown at once like a conversion chart.
- Area & Volume CalculatorArea and perimeter of flat shapes, volume and surface area of solids
- Scientific CalculatorA scientific calculator with trig, logs, powers and history
- Matrix CalculatorAdd and multiply matrices, and find the determinant, inverse, transpose, rank and RREF
- Color Contrast Checker (WCAG)Check the contrast ratio of a text and background color against WCAG 2.2 AA and AAA for normal text, large text and UI parts, and get the nearest colors that pass
- Favicon & App Icon Generator (PNG, ICO, manifest)Turn an image or one or two letters into a full favicon and app icon set, 16 to 512 px, with ICO, apple-touch-icon and a manifest snippet, saved as a zip. Nothing leaves your browser
- SVG Optimizer (Clean Up & Shrink SVG Files)Paste or upload an SVG to strip metadata, comments and editor data, round decimals and shrink the file, with a before/after size comparison and preview. Scripts and external references are removed
- GD&T Symbols Explained (Geometric Tolerances)The 14 geometric tolerance symbols from straightness to runout, datum and material condition modifiers (MMC/LMC), tolerance zone pictures and how to read a feature control frame, with search
- Thread Size Chart — pitch, pitch diameter, tap drillPitch, pitch diameter, minor diameter and tap drill size for ISO metric coarse and fine threads, UNC/UNF and pipe threads (G, R/Rc, NPT)
- Surface Roughness Chart — Ra, Rz, Rmax, N gradesConvert between Ra, Rz, Rmax, N grades and triangle finish marks, see typical roughness by machining process and how to write it on a drawing
- Beam Deflection CalculatorMaximum deflection, bending moment and bending stress of a simply supported, cantilever or fixed-fixed beam under a point or uniformly distributed load, with load, moment and deflection diagrams
- Section Properties CalculatorArea, second moment of area, section modulus and radius of gyration for rectangle, circle, pipe, I/H, channel and angle sections, with a dimension drawing; send the result to the beam and shaft calculators
- Engineering Materials TableTypical density, Young's modulus, yield and tensile strength and thermal expansion of steels, stainless steels, aluminium, copper alloys, cast iron, titanium and plastics; search, compare and send values to the other calculators
- Color Palette & Gradient GeneratorBuild matching color palettes and gradients, then copy the CSS or save an image
- Scientific Notation ConverterConvert numbers to and from scientific, engineering and E notation, and calculate with them
- Sheet Metal Gauge ChartGauge number to thickness in inches and mm for steel, galvanized, stainless and aluminum
- Scale CalculatorConvert between real size and drawing, map or model size at any scale, or find the scale from two lengths
- Gear Ratio CalculatorGear ratio, output speed and torque multiplication from tooth counts, plus spur gear dimensions from module
- Linear Interpolation CalculatorFind a value between two known points, or look up in-between values in a table, with bilinear interpolation
- Sheet Metal Bend Allowance CalculatorBend allowance, bend deduction and flat length from angle, inside radius, thickness and K-factor
- Bearing Size ChartBore, outside diameter and width of deep-groove ball bearings by number, and how to read a bearing number
- Flowchart MakerType the steps as text to draw a flowchart and save it as an image
- RPM & Gear Speed CalculatorSpeed in each gear and engine RPM at any speed from gear ratios, final drive and tyre size
- Function Grapher & Equation VisualizerGraph linear, quadratic, cubic, quartic and general functions; see roots, vertex, intercepts and intersections, derivative and tangent lines, and the area of a definite integral, with coefficient sliders