Shoe & Clothing Size Converter International size charts never agree. A men’s US 10 shoe is a UK 9.5, an EU 44, and a 28-centimeter footprint in Japan. A women’s US 6 top might map to a 34 in the EU, a 10 in the UK, and a small letter-sized S everywhere else. Rather than ...
Try the Tool »Sprint Velocity & Capacity Calculator Plan your next sprint with math, not guesswork. Feed in your velocity history, team size, PTO, and focus factor, and get an evidence-based commitment range in story points and hours. How to Use Enter your team size and sprint length in working days. Set productive hours per person per day ...
Try the Tool ».env vs .env.example Key Diff Tool Drift between your actual .env file and the .env.example template is one of the quietest sources of broken deploys. Keys get added in development, copied into production, and then forgotten in the template. Placeholder values stick around in .env where real secrets were supposed to land. This tool lines ...
Try the Tool »CSV to XML Converter Turn any CSV file into clean, well-formed XML without leaving the browser. Paste or upload your data, pick how rows and headers should map, and get back properly escaped XML with the entity edge cases (ampersands, angle brackets, quotes, embedded newlines) handled automatically. Everything runs client-side, so your CSV never leaves ...
Try the Tool »LLM API Cost Calculator Estimate what an LLM API call will actually cost before you deploy it. Enter the input tokens, output tokens, and your daily call volume, pick a model, and this tool shows you the per-call, per-day, per-month, and per-year spend across OpenAI, Anthropic, Google, and Meta models — using the current published ...
Try the Tool »DNA / RNA Sequence Generator Generate random DNA and RNA sequences with precise GC content, batch them into FASTA files, and convert between strands without leaving the browser. Built for students, bioinformatics tinkerers, and developers who need quick test data with statistical control that text-based AI assistants cannot reliably provide. How to Use Pick an ...
Try the Tool »CRC Checksum Calculator Compute Cyclic Redundancy Check values instantly for text or file input, choosing from 15 standardized variants across the CRC-8, CRC-16, CRC-32, and CRC-64 families. Verify downloads, validate serial protocol frames, or confirm file integrity without uploading anything — all calculations run locally in your browser. How to Use Type or paste text ...
Try the Tool »LLM Token Count Estimator Paste any prompt, document, or snippet of code and instantly see an estimated token count for GPT-4o, GPT-4 Turbo, GPT-3.5, the o1 reasoning models, Claude 3.x, and Gemini 1.5. The tool runs fully in the browser, updates in real time as you type, and pairs the count with cost figures per ...
Try the Tool »UUID Validator & Decoder Paste any UUID and instantly see whether it is valid, which version it follows (v1 through v8, plus the special Nil and Max UUIDs), and what metadata is hidden inside its bits. The tool decodes v1, v6, and v7 timestamps to a human-readable date, extracts the node ID / MAC fragment ...
Try the Tool »Snowflake ID Generator (Twitter-Style) Generate 64-bit Snowflake IDs using the classic Twitter bit-layout: a 41-bit millisecond timestamp, 10-bit machine/worker ID, and 12-bit per-millisecond sequence. Every ID is produced client-side with BigInt arithmetic, so nothing leaves your browser and bulk generation up to 1000 IDs stays collision-free for a single machine. How to Use Set Count ...
Try the Tool »Semver Version Calculator & Range Tester An all-in-one Semantic Versioning (SemVer 2.0.0) workbench for developers. Validate version strings, compare two versions with strict precedence, test whether a version satisfies an npm/Composer-style range expression (^, ~, x, hyphen, ||, comparison operators), bump a version with major/minor/patch/prerelease increments, and sort large lists of versions with full pre-release ...
Try the Tool »XPath Expression Tester & Evaluator Paste XML or HTML, type an XPath 1.0 expression, and instantly see which nodes match. The tester runs entirely in your browser, highlights matched fragments in the source, and shows a readable summary for node sets, strings, numbers, and booleans. How to Use Paste your XML or HTML document into ...
Try the Tool »CUID2 Generator Generate cryptographically secure CUID2 IDs entirely in your browser. CUID2 is a modern, collision-resistant identifier format that combines a high-entropy random salt, monotonic counter, timestamp, and browser fingerprint, then runs the result through SHA3-512 to produce a base36 string. Every ID starts with a letter, so values stay safe to use in databases, ...
Try the Tool »Identicon / Avatar Generator Turn any string — a username, email, user ID, or wallet address — into a unique visual avatar. The Identicon / Avatar Generator hashes the input deterministically, so the same text always renders the exact same image. No upload, no account, no server round-trip: the avatar is drawn entirely in your ...
Try the Tool »PWA Web App Manifest Generator Build a valid manifest.json file for your Progressive Web App in seconds. Fill in your app’s identity, choose a display mode, pick the icon sizes you ship, and the generator produces clean JSON you can drop straight into your project — plus the matching <link rel="manifest"> tag for your HTML. ...
Try the Tool »Fake Email Address Generator Generate realistic-looking fake email addresses for testing, development, and prototyping. This tool creates syntactically valid email addresses using common name patterns and popular domain names, perfect for populating test databases, demo environments, or form testing without using real email addresses. How to Use Select your preferred email format from the dropdown, ...
Try the Tool »Sales Tax & VAT Calculator Instantly calculate sales tax and VAT on any price. Enter an amount and tax rate to see the pre-tax price, tax amount, and total. The calculator supports both adding tax to a price and removing tax from a tax-inclusive total (reverse VAT), making it useful for invoicing, receipt verification, and ...
Try the Tool »Docker Run to Docker Compose Converter Quickly convert any docker run command into a clean docker-compose.yml file. This tool parses your CLI command and generates a properly structured Compose configuration, saving you from manually translating complex flags and options. How to Use Paste your docker run command into the input field. The tool instantly parses ...
Try the Tool »XML to JSON Converter Convert XML data to JSON format instantly with this free online tool. Whether you are working with API responses, configuration files, or data exports, this converter handles nested elements, attributes, and complex XML structures with ease. How to Use Paste your XML content into the input area or click “Try an ...
Try the Tool »Phone Number Parser and Formatter Parse and format phone numbers into standard international formats instantly. Enter any phone number in any format and get it converted to E.164, national, international, and RFC 3966 formats. The tool also detects the country, validates the number, and identifies the number type (mobile, fixed line, toll-free, etc.). How to ...
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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 May 14, 2026
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