CAGR Calculator The CAGR Calculator finds the compound annual growth rate of an investment, business metric, or any value that grows over time. Enter a starting value, an ending value, and the number of years, and the tool computes the smooth annual rate that would carry the start to the end if it grew at ...
Try the Tool »HAR File Formatter & Request Inspector Drop in an HTTP Archive (.har) file exported from your browser’s DevTools and instantly see every request as a sortable, filterable waterfall — with full DNS, connect, SSL, wait, and download timings, plus the raw headers, body, and a ready-to-paste cURL command for any single request. Everything runs locally ...
Try the Tool »NDJSON Formatter & Validator Paste a Newline-Delimited JSON (NDJSON / JSON Lines) document and check every record at once. Each line is parsed independently, so a single broken record does not hide the rest. The tool reports valid and invalid line counts, the most common top-level keys, and the exact parse error for any line ...
Try the Tool »Base64 Image Preview & Decoder Paste a base64-encoded image string and instantly preview the rendered image, with the format auto-detected from the file’s magic bytes. The decoded image, its pixel dimensions, and the decoded byte size are all computed in your browser – no server upload, no waiting on an API. The optional data: URI ...
Try the Tool »Package.json Formatter & Key Sorter Paste any package.json to get a clean, canonical-ordered version back instantly. This tool reorders top-level keys to the standard npm sequence (name, version, description, scripts, dependencies, and so on), validates required and recommended fields, checks your dependency version ranges, and flags non-standard keys that clutter the manifest. Everything happens in ...
Try the Tool »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. ...
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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 18, 2026
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