Cryptocurrency Converter
Convert between thousands of cryptocurrencies and major world currencies using live rates. No account, no sign up, no limits.
How this crypto converter fetches live prices and turns every unit into a common USD yardstick
This is not a static calculator with a fixed rate baked into the page. It calls CoinGecko’s public REST API to pull real market prices, no account and no API key required. What makes it cheap to run at scale is how sparingly it calls that API, everything else is arithmetic done entirely in your browser.
On load, the tool makes exactly two kinds of requests: two paginated calls to coins/markets for the top 500 coins by market cap, which returns each coin’s current USD price and 24 hour change in the same response, and one call to simple/price that prices Bitcoin against every fiat currency and metal the tool offers. Both responses are cached in localStorage for 24 hours. Every conversion you run after that first load, and every conversion for the rest of the day, is computed from that cached data with zero additional network calls.
The bridge-through-USD method
CoinGecko does not have a dedicated exchange rate endpoint for every possible pair, coin to coin, coin to fiat, fiat to metal. Rather than fetching a rate for each combination, the tool expresses every single unit it knows about as one number: how much one unit of that thing is worth in US dollars. A conversion between any two units then becomes simple division.
current_price field from the markets endpoint is already denominated in USD, so this step is a direct lookup.
Worked example, using illustrative prices: if 1 BTC equals $65,000 on the cached markets data, and 1 ETH equals $3,250, then the bridge math gives 1 BTC equals 65000 divided by 3250, or 20 ETH, without ever calling an endpoint that prices Bitcoin directly in Ethereum.
| What’s cached | Source endpoint | Refresh interval |
|---|---|---|
| Top 500 coin prices | coins/markets (2 pages) | 24 hours, or manual refresh |
| BTC price in ~44 fiat and metal units | simple/price | 24 hours, or manual refresh |
| Bits and satoshis | computed locally, not fetched | derives from BTC on every conversion |
The search combobox
Why not a native select
With over 500 coins plus roughly 44 fiat and reference units, a plain HTML select becomes slow to scroll and its built in type-to-search behavior does not render consistently across every browser and mobile picker. The tool builds a small custom combobox instead, a text input with a filtered dropdown underneath.
How it behaves
Typing filters the list in place by label, matching against both name and ticker symbol. Clicking an entry or pressing Enter selects it. Pressing Escape, or clicking away from the input, reverts the field back to whatever was last actually selected, so a half-typed search never silently becomes your conversion input.
What else is shown
When the amount you are converting from is a coin, the tool also shows that coin’s 24 hour percentage change, taken directly from the same cached markets response, no separate request needed. Your last selected pair is remembered in localStorage so the tool reopens where you left it.
Cryptocurrency prices are volatile and this tool reflects cached market data, not real time trading prices suitable for executing a trade. It is for reference and estimation only, not financial advice.
- CoinGecko API documentation describes the markets and simple price endpoints this tool calls.
- Investopedia: Cryptocurrency for background on how crypto markets and pricing work generally.
- MDN: Window.localStorage documents the browser storage API this tool uses for caching.
What people check before trading
Sanity checking a price before manually placing a trade elsewhere, converting a coin balance into a familiar fiat figure for a quick portfolio estimate, working out how many satoshis a small purchase amount represents, comparing two altcoins directly against each other, or converting a Bitcoin holding into gold ounces as a rough store of value comparison.
FAQ: Cryptocurrency Converter
Every conversion sends a live request to the pricing API at the moment you ask for it. Nothing is cached or delayed, so the number you see reflects the current rate, not a snapshot from earlier in your visit.
The dropdown covers thousands of cryptocurrencies alongside dozens of major world currencies including the US Dollar, Euro, British Pound, Turkish Lira, and more. Type into either search box to filter the list down quickly.
Coverage depends entirely on the pricing API behind this tool. Extremely small or newly listed coins, or less common fiat currencies, may not have a live rate available yet. Try a different currency on one side of the conversion.
This tool is meant for quick reference conversions, not for executing trades. Actual exchange rates on a trading platform will include spreads and fees not reflected here, so treat the numbers as an informative estimate rather than an exact execution price.
No. This converter is free to use with no account and no sign up required on your end. It already has an API connection built in behind the scenes.
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