Merkle Tree Generator & Visualizer Paste a list of values, choose a hash function, and instantly see a visual Merkle tree with every intermediate node hash and the final Merkle root. Pick SHA-256, SHA-1, or Keccak-256 (the hash Ethereum uses), tune the Bitcoin-style odd-leaf rule or the OpenZeppelin sorted-pair convention, and export the full tree ...
Try the Tool »GPU VRAM Calculator Estimate how much GPU memory a transformer model needs for inference or training. Enter parameters, precision, batch size, and sequence length, and the calculator returns total VRAM along with a breakdown of weights, gradients, optimizer state, KV cache, and activations. It also compares the result against common GPUs (RTX 4090, A100, H100, ...
Try the Tool »Julia Code Formatter Paste any Julia (.jl) source and get instantly reformatted output following the conventions used by the wider Julia scientific-computing community. The tool runs entirely in your browser — no Julia runtime, no server round-trip — so even confidential research or proprietary code can be cleaned up safely. The formatter mirrors the default ...
Try the Tool »Wire Size Calculator (AWG & mm²) Pick the right copper or aluminum conductor for any DC, single-phase AC, or 3-phase AC circuit. Enter your load current, supply voltage, and one-way cable length and the calculator iterates the NEC ampacity table to find the smallest wire that handles the load and keeps voltage drop under your ...
Try the Tool »Rule of 72 Calculator A fast, two-way doubling-time calculator. Enter an annual rate to see how many years money takes to double, or enter a target number of years to see the rate you need. The tool compares the classic mental-math shortcuts (Rule of 72, 70, and 69.3) against the exact compound result derived from ...
Try the Tool »Number Notation Converter Paste a number in any common notation and instantly see how it looks in every other one. Useful when you copy a figure out of a German invoice into a US spreadsheet, when an Indian accountant hands you a balance in lakhs, or when a paper expresses something in scientific notation that ...
Try the Tool »ASCII Box Table Generator Paste CSV or tab-separated data and instantly turn it into a clean, fixed-width table built from Unicode box-drawing characters. The generator auto-sizes each column to fit the widest cell, so borders always line up no matter how irregular the source data is. Drop the result straight into READMEs, code comments, terminal ...
Try the Tool »Leet Speak (1337) Text Converter Convert any plain text to leet speak (also known as 1337 or hackspeak) in your browser, with three intensity levels and a reverse decoder. The tool swaps letters for numbers and symbols using deterministic lookup tables, so the same input always produces the same output unless you opt in to ...
Try the Tool »Anagram Generator Type any word or short phrase and instantly see every valid English anagram it can form. The generator runs entirely in your browser against a curated dictionary of common English words, so there are no API calls, no rate limits, and no data leaves your device. It supports single-word lookups, two-word and three-word ...
Try the Tool »SWIFT/BIC Code Validator & Parser Paste any SWIFT or BIC code to validate its structure against the ISO 9362 specification and break it into its component parts. The tool checks character patterns, length, and identifies whether the code refers to a head office or a specific branch — all client-side, with no data ever leaving ...
Try the Tool »Directory / Folder Tree Generator Turn a plain indented file list or a set of slash-separated paths into a clean ASCII directory tree with proper box-drawing characters. Perfect for READMEs, technical documentation, blog posts, and code reviews where a visual project structure communicates more than a flat list of file paths. How to Use Paste ...
Try the Tool »Musical Note Frequency Generator Convert any musical note to its exact frequency in hertz, MIDI note number, and wavelength — or go the other way and find the nearest note for any frequency you enter. An interactive piano keyboard lets you click any key to hear the tone through your browser, and you can switch ...
Try the Tool »Playfair Cipher Encoder & Decoder Encrypt or decrypt text with the classic Playfair cipher entirely in your browser. Enter a keyword, paste your plaintext or ciphertext, and watch the tool build the 5×5 keyed matrix, prepare the digraphs, and walk through every substitution step. No data ever leaves your device. How to Use Pick a ...
Try the Tool »Photography Exposure Value (EV) Calculator Dial in the exposure triangle without leaving the browser. Pick any two of aperture, shutter speed, and ISO and the calculator solves for the third, displays the resulting EV, and lays out every equivalent combination at the same exposure. A built-in scene reference based on the classic Sunny 16 rule ...
Try the Tool »Ethereum / EVM Address Checksum Validator Paste any Ethereum or EVM-compatible address and instantly check whether its mixed-case checksum is correct under EIP-55. The tool also returns the canonical checksummed form so you can copy a safe version back into your wallet, contract, or block explorer. Everything runs locally in your browser — no addresses ...
Try the Tool »Hardness Scale Converter Convert a single hardness measurement across the Mohs, Vickers (HV), Brinell (HB), and Rockwell A / B / C scales in one click. The converter uses ASTM E140 lookup data (with linear interpolation between rows) for the steel scales, plus a log-linear fit between Mohs and Vickers so you can compare metals ...
Try the Tool »Word Cloud Generator Paste any block of text and instantly turn it into a frequency-weighted word cloud. Bigger words appear more often, and you can shape, color, and rotate the layout — then download the result as a high-resolution PNG or a clean, infinitely scalable SVG. How to Use Paste or type your text into ...
Try the Tool »Heat Index & Wind Chill Calculator Find out what the weather really feels like. This calculator combines temperature with humidity (for hot days) or wind speed (for cold days) to produce a “feels like” temperature using the official NOAA / National Weather Service formulas, then maps the result to a color-coded safety category so you ...
Try the Tool »Print & Typography Units Converter A live, bi-directional converter for the units designers, print professionals and front-end developers reach for every day: points, picas, pixels, millimetres, centimetres, inches, em and rem. Type into any unit and the rest update instantly using the DPI and font size you choose, so values match the actual medium you ...
Try the Tool »Multi-Base Arithmetic Calculator (Hex / Binary / Octal) Add, subtract, multiply, divide, and take the modulo of numbers written in binary, octal, decimal, or hexadecimal — and see the answer in all four bases at once. The calculator uses arbitrary-precision BigInt arithmetic, so large hexadecimal values stay exact, and it visualises the carry, borrow, shift-and-add, ...
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Scoreboard is a fun way to keep track of your games, all data is stored in your browser. More features are coming soon!
Update: Our latest tool was added on Jun 21, 2026
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