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CryptoTools โ https://cryptotools.tech โ A growing suite of 30+ free, single-purpose crypto & finance tools. Three families: calculators (Bitcoin DCA backtest, profit/P&L + tax, mining, portfolio/tax CSV, staking, leverage, liquidation, position size, impermanent lossโฆ), converters (gweiโETH + gas fee, satoshiโUSD, hashrate), and a privacy-first cryptography toolkit that runs 100% in your browser โ nothing is ever uploaded (SHA-256/keccak hashing, AES, RSA & key generators, BIP39 seed phrases, HD wallet addresses, JWT decoder, plus EVM/ENS/EIP-712 dev tools and more). Plus interactive Bitcoin data studies (DCA backtests, "what if you missed the best days", a monthly-returns heatmap). No sign-up, no tracking, no paywalls; pure static site with sub-second loads; works in 10 languages; every tool is embeddable. For traders, builders, and the privacy-conscious who want a fast answer without a bloated SaaS dashboard.
StringFlux CryptoTools.techCryptoTools.tech's answer:
CryptoTools.tech's answer:
CryptoTools.tech is a single, fast home for 30+ free crypto & finance tools โ calculators, converters, and a full cryptography toolkit โ with no sign-up, no tracking, and no paywalls. What sets it apart: every cryptography tool (hashing, AES, RSA, BIP39 seed phrases, HD wallets, JWT decoding, EVM/ENS dev utilities) runs 100% in your browser โ your keys and data never touch a server. It uniquely covers both meanings of "crypto" โ cryptocurrency calculators and cryptography utilities โ under one roof, in 10 languages, with every tool embeddable.
CryptoTools.tech's answer:
Most crypto tool sites make you sign up, bury the tool under ads and pop-ups, or send your input to a server. CryptoTools is the opposite: privacy-first (client-side cryptography โ nothing is uploaded), instant (static pages, sub-second loads, clean UI), and completely free with no account. You also get both worlds in one place โ finance calculators (profit/P&L, DCA backtests, mining, tax) and developer/cryptography utilities โ across 10 languages, with the formulas shown so you can trust the math. If you value speed, privacy, and not being upsold, it's the cleaner choice.
CryptoTools.tech's answer:
Three overlapping groups: (1) crypto traders & investors who need quick, reliable calculators (profit, DCA, position sizing, liquidation, tax estimates); (2) developers & web3 builders who need cryptography and Ethereum utilities (hashing, AES/RSA, BIP39, JWT, EVM bytecode, ENS namehash, EIP-712); and (3) privacy- and security-conscious users who want tools that run locally and never upload their data. It's global and multilingual, skewing toward technically literate, self-serve users who want an answer without a bloated dashboard.
CryptoTools.tech's answer:
It started from a simple frustration: every "crypto calculator" wanted a sign-up, was slow and ad-choked, or quietly sent your data to a server. So CryptoTools was built as the tool site I wished existed โ fast, free, private, no account โ and grew into a broad cluster spanning both cryptocurrency calculators and cryptography utilities. It's an independent, bootstrapped project with a simple principle: do one thing well per page, and respect the user's time and privacy.
CryptoTools.tech's answer:
Built with Astro (static-site generator, ships zero JS by default) and Preact "islands" for interactivity โ so pages are pure static HTML/CSS/JS with sub-second loads and green Core Web Vitals. Cryptography runs in-browser via audited libraries (@noble/hashes, @noble/curves, @scure/bip39/bip32) and the Web Crypto API. Served by Caddy (automatic HTTPS, HTTP/2+3) on Docker, with a thin optional backend only for live/historical price data. Fully internationalized into 10 languages.
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