Crypto tools that just work

Free crypto profit calculator: enter buy and sell price, amount and fees to get profit, loss and ROI. Works for any coin, right in your browser.

Backtest dollar-cost averaging into Bitcoin — or Ethereum, Solana and other major coins — and see what regular buys would be worth today.

Crypto staking calculator for APY, compounding and lock-up periods. See what a stake actually returns after compounding, in your browser, free.

Crypto compound interest calculator: starting balance, rate and contributions, compounded daily to yearly. See the curve, not just the total.

Impermanent loss calculator for any AMM pool. Enter the price change and see the loss against simply holding, with the formula shown. Free, no sign-up.

Liquidation price calculator for long and short positions: entry, leverage and maintenance margin in, liquidation price out. Free and in-browser.

Crypto position size calculator: account size, risk percentage and stop distance in, position size and margin out. Free, no sign-up, in your browser.

Crypto leverage calculator for margin, liquidation distance and effective exposure. See what a given leverage really costs you. Free, in-browser.

Crypto average calculator for your entry price: add every buy, get the weighted average cost and break-even. Free, no sign-up, runs in your browser.

Mining profitability calculator: hashrate, power draw, electricity price and pool fee in, daily and monthly profit out. Free and in-browser.

Crypto tax calculator for capital gains: FIFO, LIFO or average cost, with short and long term split out. Runs in your browser, nothing uploaded.

Crypto portfolio tax CSV analyser: drop an exchange export and get holdings, cost basis and realised gains. Parsed in your browser, never uploaded.

Convert mining hashrate between H/s, kH/s, MH/s, GH/s, TH/s, PH/s and EH/s instantly. A fast, free hashrate unit converter that runs in your browser.

Gwei to ETH converter, and back — plus wei and a live gas-cost estimate. Type in any unit and the rest update. Free and entirely in your browser.

Convert satoshis (sats) to USD and BTC instantly at any Bitcoin price you set — and back again. Fast, free, no sign-up, runs in your browser.

Hash generator online for SHA-256, SHA-512, Keccak-256, RIPEMD-160 and MD5, from text or hex. Runs in your browser — nothing is ever uploaded.

AES encryption online with AES-GCM and a password-derived key. Encrypt and decrypt text in your browser via WebCrypto — nothing is uploaded.

Crypto address validator for Bitcoin and Ethereum: checks the checksum, the format and the network, and tells you which one it is. Free, in-browser.

Base64, hex and base58 converter in one place, plus UTF-8 and binary. Convert between any pair in your browser — nothing leaves your machine.

BIP39 seed phrase generator and validator: 12 or 24 words, with checksum verification and the derived seed. Generated in your browser, never sent.

Password generator using your browser's own CSPRNG: length, character sets and an entropy readout in bits. Nothing is uploaded or stored anywhere.

JWT decoder for header, payload and signature, with expiry and issued-at rendered as real dates. Decodes in your browser — no token is ever uploaded.

HD wallet address generator: a BIP39 mnemonic to BIP32/44/84 addresses with the derivation path shown. Derived in your browser, never transmitted.

RSA key generator for 2048, 3072 and 4096-bit keypairs in PEM, via your browser's WebCrypto. The private key is generated locally and never leaves it.

Sign and verify a message with secp256k1 ECDSA, the Bitcoin and Ethereum way. Signed in your browser — the private key never leaves your machine.

Bitcoin QR code generator for addresses and BIP21 payment URIs, with an amount and label. Rendered in your browser — no address is ever uploaded.

Merkle root calculator: paste leaves, get the root and the full SHA-256 tree with every proof path. Computed in your browser, nothing uploaded.

EVM bytecode disassembler: paste hex, get readable opcodes with push data and jump destinations resolved. Runs in your browser, free, no sign-up.

Vanity address generator for Ethereum: pick a prefix and grind it in your browser with Web Workers. The key is generated locally and never sent.

Ethereum function selector and event topic calculator: paste a signature, get the 4-byte selector and the keccak256 topic. Free and in-browser.

ENS namehash calculator: get the namehash and labelhash for any .eth name, with every level of the recursion shown. Computed in your browser, free.

Proof of work demo: pick a difficulty and watch the nonce grind until the hash beats the target. Mining made visible, in your browser, free.

EIP712 hash calculator for typed structured data: paste the JSON, get the domain separator, struct hash and final digest. Runs in your browser.

Elliptic curve visualizer for point addition and doubling over a small prime field. See why ECC works, plotted point by point, in your browser.

Shamir secret sharing in your browser: split a secret into N shares needing M to rebuild, then recombine them. Nothing is uploaded, ever.

Raw transaction decoder for Ethereum: paste RLP hex to get every field plus the recovered sender address. Decoded in your browser, never uploaded.

A crypto chart game: guess the coin and the year from a real, unlabelled price chart in five tries. One new chart a day, everyone gets the same one.

A daily code bug puzzle: one real snippet, exactly one bug, five guesses. Everyone gets the same one each day. Free, no sign-up, in your browser.

A daily standup game: five things get said to you, three ways to answer each, one shareable grid. Same standup for everyone that day. Play today's in a minute.

A crypto endless runner game down the blockchain. Jump the stale blocks, dodge the orphans, collect nonces and seal blocks. Free, runs in your browser.

A bitcoin history game: twelve decisions from the first decade — the pizza, the exchange, the landfill — and five endings. Free, no sign-up.

A big O complexity quiz: read five real snippets, name the complexity, then see your guess and the answer plotted on the same curve. Free.

A logic gate puzzle game: wire AND, OR, XOR, NAND and NOR into a circuit that matches the truth table. There is no NOT gate — build one. Free.

A sorting algorithm visualizer game: two algorithms race on the same array and you bet on the winner. The better big-O is a coin flip. Free.

An on call incident game: triage alerts by impact, deploy age and runbook, and learn which mistake costs more. Free, no sign-up, in your browser.

A programmer typing game: type real identifiers and keywords before they reach the bottom. WPM is timed within each word. Free, no sign-up.

A firewall game: drop the bad packets and pass the good ones. Blocking everything takes the service down as fast as blocking nothing. Free.

A tech debt game: ship features fast and watch the debt slow you down, or pay it off and ship less. An incremental game where the loop is the point.

A legacy code game: you inherit a codebase nobody wants and every option is a trade you cannot undo. Nine endings. Free, no sign-up, in-browser.

A vanity address benchmark disguised as a game: grind an Ethereum prefix with every core and see your keys per second. Nothing leaves the browser.

A garbage collector game: mark what is reachable from the roots and sweep the rest. Reachability made visual. Free, no sign-up, in your browser.

A lock ordering puzzle: acquire the locks in an order that makes a cycle impossible. Watch the wait-for graph resolve, or deadlock. Free, no sign-up.

Reach the target point on a real elliptic curve using only doubling and addition. A puzzle game that teaches the double-and-add algorithm behind crypto keys.

A crypto higher or lower game: two coins, one price each, guess which is worth more. Endless run, one wrong answer ends it. Free, no sign-up.