Crypto, web, finance and app data tools

Details of a mobile app on the App Store or Google Play by id, package name or store URL: developer, developer email, rating, installs, price, genre and update date. Use for app or competitor research.

User reviews of a mobile app from the Apple App Store or Google Play, by app id, package name or store URL: rating, text, date, version and developer reply, plus rating counts. Use to analyse app feedback.

Search the App Store or Google Play (store: google or apple) for a keyword and get up to 50 apps in rank order with full details. Use for ASO keyword research or finding competing apps.

Search arXiv preprints (AI, physics, math, CS, quant finance...) by keywords or field query: title, authors, abstract, categories, dates and PDF link, by relevance or newest. Use for literature review or tracking new research.

Battery storage (BESS) day-ahead arbitrage revenue for a European bidding zone over up to a year of historical prices: annualised revenue per MW, cycles and payback. Use when sizing or screening a battery project or comparing zones. Dates are YYYY-MM-DD.

Balance of a Bitcoin address (confirmed and pending), total received and sent, transaction count and its latest 10 transactions with net amount. Use to check a BTC payment or wallet.

Bitcoin network fee rates in sat/vB for next block, 30 minutes, 1 hour and economy, plus mempool size, block height and the cost of a typical payment. Use right before sending BTC.

Status of a Bitcoin transaction: confirmed or pending, confirmations, block, time, fee and fee rate, RBF flag, inputs and outputs. Use to confirm a BTC payment or decide whether to bump a fee.

Find books by title, author or ISBN (Open Library): authors, first publication year, editions, pages, ISBNs, subjects, publishers, languages, rating and cover image. Use for book lookups, reading lists or metadata.

Blockchains ranked by DeFi total value locked with share of the market, gas token and chain id. Use to compare ecosystems (Ethereum, Solana, Base, Arbitrum...) or track where capital is moving.

Facts about a country by name or ISO code: official name, capital, region, languages, currencies, calling code, borders, area, internet TLD, coordinates, UN membership and flag. Use to enrich addresses, forms and datasets.

OHLCV candles for a crypto pair from Coinbase Exchange at 1m, 5m, 15m, 1h, 6h or 1d, up to 300, oldest first. Use for charting, technical indicators (RSI, moving averages) and backtests.

Full profile of a coin by symbol or CoinGecko id: description, website, X/Twitter, GitHub, categories, contract addresses per chain, price, market cap, FDV, volume, 24h/7d/30d/1y change, all-time high/low and supply. Use for token research or due diligence.

Convert an amount of any token (BTC, ETH, SOL, symbols or chain:address) into one or more fiat currencies (USD, EUR, GBP, AED, JPY, ~35 more), with the price per unit each way. Use for invoices, accounting or pricing in local currency.

Centralized crypto exchanges ranked by trust score or adjusted 24h volume: name, volume, markets, supported fiat currencies, website and notices such as hacks. Use to pick a venue or check one.

The Crypto Fear & Greed Index (0 extreme fear to 100 extreme greed) for today, with up to a year of daily history. Use as a market-sentiment signal for trading, newsletters or answering how the crypto market feels.

Total crypto market capitalisation, 24h volume, Bitcoin dominance, 24h change and distance from the all-time high, in one call. Use for a market summary or risk-on/risk-off context.

Latest crypto news from CoinDesk, Cointelegraph, Decrypt and The Block in one feed, newest first, with title, link, time, summary and tags; filter by keyword or coin (BTC, ETH, SOL, ETF, Base). Use to explain a price move, brief a trader or monitor a project.

Daily USD price history of any token (symbol, CoinGecko id or chain:address) for up to 365 days with high, low and % change, or its exact price on a past date. Use for charts, backtests, cost basis or 'what was ETH worth on...' questions.

Current USD price and 24h change for up to 20 crypto tokens per call, by symbol (BTC, ETH, SOL, PEPE), CoinGecko id or chain:contract address (base:0x833589..., ethereum:0x...). Covers thousands of coins and on-chain tokens. Use for portfolio valuation, trading decisions or answering what a token costs now.

Top cryptocurrencies by market cap (up to 250) with price, 1h/24h/7d change, volume, all-time high and supply, optionally within a CoinGecko category (layer-1, meme-token, artificial-intelligence, real-world-assets). Use for market overviews and screeners.

Coins trending on CoinGecko right now (most searched in 24h) with price, 24h change, market cap and volume, plus trending categories. Use to spot what retail is looking at or find narratives gaining attention.

Details of a CVE by id: description, CVSS score, severity and vector, CWE, whether it is in CISA's Known Exploited list, affected products (CPE) and references, from NVD with CVE.org fallback. Use for security triage and patch prioritisation.

Supply and borrow APYs across DeFi lending markets (Aave, Compound, Morpho, Spark, Venus...) by token, chain or protocol: net borrow rate, utilisation, TVL, total borrowed and max LTV. Sort by supply_apy, borrow_apy (cheapest first) or tvl. Use to find the best place to lend or borrow.

DeFi protocols by total value locked (DefiLlama): look up one protocol (aave, uniswap, lido) or rank them by chain and category (Lending, Dexs, Liquid Staking, Bridge...) with TVL, 1d/7d change, market cap and chains. Use for DeFi research and protocol comparisons.

Best DeFi yields right now: lending, staking and liquidity pools across all chains and protocols, with APY (base + rewards), 30-day mean APY, TVL, stablecoin flag and impermanent-loss risk. Filter by chain, protocol, token and minimum TVL; sort by APY or TVL. Use to find where to earn on USDC, ETH etc.

English dictionary entry for a word: pronunciation (IPA and audio), parts of speech, definitions with examples, synonyms and antonyms, from Wiktionary. Use for writing, learning or word games.

Detect the language of a text among 55 languages, with probabilities for each candidate and a reliability flag. Use to route messages, pick a translator or tag content.

DEX trading pairs for a token symbol, name or contract address across all chains (DexScreener): price, liquidity, 24h volume, 1h/24h change, buys/sells, FDV, market cap and pair age, deepest liquidity first. Use to price new or small tokens and check if they can be traded.

Decentralized exchange volume: total market 24h/7d and the top DEXs (Uniswap, Aerodrome, Raydium...) with 24h, 7d, 30d volume and daily change, for all chains or one chain. Use to compare DEX activity or chain usage.

DNS records of a domain: A, AAAA, MX, TXT, NS, CNAME, SOA and CAA, plus SPF and DNSSEC status, via Cloudflare/Google DNS-over-HTTPS. Use to check where a domain points, its mail servers, verification TXT records or why email or a website is failing.

Check up to 20 domain names at once, or one name across several TLDs (com, ai, io...), for registration via RDAP and DNS: available or taken, registrar and expiry. Use for brainstorming product names and finding free domains.

Registration data of a domain from RDAP, the official WHOIS successor: registrar, creation, update and expiry dates, status codes, nameservers, DNSSEC and registrant organisation/country where public. Says whether an unregistered name looks available. Use for domain research, due diligence or phishing checks.

Recent earthquakes worldwide or within a radius of a point (USGS): magnitude, place, time, depth, tsunami flag, PAGER alert and felt reports, over the last hour, day, week or month. Use for risk monitoring and news.

Check an email address before sending: syntax, whether the domain exists and has mail servers (MX), disposable/temporary provider, role address (info@, sales@), free provider and typo suggestion (gmial.com -> gmail.com), with a verdict. No mail is sent and the mailbox is not probed.

Resolve an ENS name (vitalik.eth) or Basename (jesse.base.eth) to its address and profile records (avatar, url, twitter, github, email, description), or an address to its verified primary name. Use before sending funds to a name or to show who owns a wallet.

Facts about an ERC-20 contract read from the chain (Ethereum, Base, Arbitrum, Optimism, Polygon): name, symbol, decimals, total supply, USD price and fully diluted value. Use to verify a token address before trading or integrating it.

Latest electricity generation by source (MW) for a European country (DE, FR, NL, PL, IT, AT, CH, BE...): wind, solar, nuclear, gas, coal, hydro, batteries, total load, net imports, renewable share and CO2 intensity. Use for energy dashboards, trading context or emissions reporting.

Day-ahead wholesale electricity prices for a European bidding zone (DE-LU, FR, NL, AT, BE, PL, ...) for up to 31 days in local time, with daily min/max/mean and the cheapest and priciest N-hour window. Use when scheduling EV charging, heat pumps or batteries, or asked what power costs tomorrow.

Validate an EU VAT number live against the official EU VIES service, returning valid/invalid and the registered company name and address where the member state shares them. Use for B2B invoicing, reverse charge checks and KYC. Unavailable member states return an error and are not charged.

Look up any EVM chain by chain ID or name (8453, base, arbitrum): chain ID in decimal and hex, native currency, public RPC URLs, block explorers and testnet flag. Use to configure wallets, RPCs or cross-chain apps.

Current gas fees on Ethereum, Base, Arbitrum, Optimism or Polygon: base fee and slow/standard/fast priority and max fee in gwei plus the cost of a plain transfer. Use before sending a transaction.

Status of an EVM transaction by hash: pending, success or failed, block, confirmations, timestamp, from/to, value, gas used, fee (plus L1 fee on Base/Optimism) and ERC-20 token transfers. Searches Ethereum, Base, Arbitrum, Optimism and Polygon if no chain is given. Use to confirm a payment settled.

Balances of a wallet address or ENS name on Ethereum, Base, Arbitrum, Optimism and Polygon in one call: native ETH/POL, USDC, USDT, DAI and any ERC-20 contracts you add, each with USD value and a total. Use to check whether a wallet is funded, value a portfolio or confirm a payment arrived.

Live spot price of a crypto pair on Coinbase and Kraken: bid, ask, last, 24h open/high/low and volume, and the price gap between the two exchanges. Use for an exact executable price or a quick arbitrage check.

Every link on a web page with its anchor text, split into internal and external, with nofollow flags and the most-linked external domains. Use for SEO audits, crawling, backlink research or broken-link checks.

Food product details from its EAN/UPC barcode: name, brand, quantity, ingredients, allergens, Nutri-Score, NOVA processing group, Eco-Score and nutrients per 100 g, from Open Food Facts. Use for nutrition apps, shopping assistants or allergy checks.

Any FRED economic time series by id or alias: CPI, core PCE, unemployment, payrolls, GDP, fed funds, SOFR, Treasury yields, mortgage rates, M2, oil, VIX, jobless claims... Latest value, change, 1-year % change and history. Use for macro analysis and economic questions.

Search openly licensed images (Creative Commons and public domain) from Flickr, Wikimedia and museums via Openverse: image URL, size, creator, license and a ready-made attribution line. Filter to commercially usable images. Use to illustrate posts, slides or sites legally.

Official ECB reference exchange rates for about 35 currencies (USD, EUR, GBP, JPY, CNY, INR, AED, SAR and more) for today or any date since 1999, from any base currency, with optional amount conversion. Use to convert prices, invoices or salaries between currencies.