canonical: https://jentic.com/apis/coinlayer.com/coinlayer

# Coinlayer

Coinlayer is a lightweight cryptocurrency exchange-rate API focused on simple, JSON-formatted price data. Six REST endpoints cover live rates, historical rates, time-series data over a date range, percentage change calculations, currency conversion, and the catalogue of supported coins. It is designed for applications that need straightforward crypto pricing without the complexity of full exchange-level data.

## For AI agents

Look up live, historical, time-series, and converted cryptocurrency exchange rates against fiat or other crypto via a simple JSON REST API.

## Scope

Does not handle order placement, wallet management, or on-chain operations - use for cryptocurrency exchange rate lookups and conversions only.

## Capabilities

- Retrieve live exchange rates for any supported cryptocurrency against a chosen target
- Pull historical exchange rates for a specific past date
- Fetch a daily time-series of rates between two dates for one or more coins
- Calculate percentage rate change between two dates for chosen coins
- Convert an amount between any two supported currencies in a single call
- List all coins and target currencies supported by Coinlayer

## Use cases

### Lightweight Crypto Pricing for Apps

Embed live and historical crypto prices in apps, sites, and dashboards without setting up exchange integrations. Coinlayer returns simple flat JSON for the live and historical endpoints, making it trivial to surface a price next to a fiat amount. Integration usually takes well under an hour.

Example prompt: Call GET /live with symbols=BTC,ETH and target=USD and return the rates

### Crypto-to-Fiat Currency Conversion

Convert any amount between supported currencies - crypto-to-fiat, fiat-to-crypto, or crypto-to-crypto - in a single call. Useful for invoicing tools, donation widgets, and payment summaries that need to show an equivalent in another currency.

Example prompt: Call GET /convert with from=BTC, to=USD, and amount=0.5 and return the converted value

### Historical and Time-Series Crypto Reporting

Build crypto reports and charts using historical and time-series endpoints. Pull daily rates between two dates with /timeframe, or compute percentage change with /change for highlight calculations. Suitable for newsletters, blogs, and monthly reports.

Example prompt: Call GET /timeframe with start_date and end_date and symbols=BTC,ETH to retrieve a daily rate series

### AI Currency Assistant via Jentic

Build an AI assistant that converts amounts between crypto and fiat through Jentic. The agent expresses an intent (convert this amount, look up yesterday's rate); Jentic resolves the right Coinlayer endpoint and executes the call with stored credentials. A good fit for low-volume conversion features in chat UIs.

Example prompt: Through Jentic, convert 1 BTC to USD using the live rate and return the value with timestamp

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| GET | `/live` | Get current exchange rates for selected coins |
| GET | `/historical` | Get rates for a specific past date |
| GET | `/timeframe` | Get daily rate series between two dates |
| GET | `/convert` | Convert an amount between two currencies |
| GET | `/list` | List supported coins and target currencies |

## Key resources

- **Live Rates** — Current exchange rates for supported coins
- **Historical Rates** — Exchange rates on a specific past date
- **Timeframe** — Daily rate series between two dates
- **Change** — Percentage change in rates between two dates
- **Convert** — Convert an amount between two currencies
- **List** — Catalogue of supported coins and target currencies

## Why Jentic

- **Setup:** Wiring Coinlayer by hand means appending its access_key to every query against the api.coinlayer.com host and handling the live, historical, and conversion endpoints yourself. Through Jentic you install once, import Coinlayer from the API Directory, store the key once, and your agent calls it.
- **Permission scoping:** Coinlayer serves read-only exchange rate lookups, so you scope by choosing the operations the agent may call: limit it to what it needs, such as fetching live rates or converting between coins, and calls like timeframe history are not included unless you add them.
- **Credential handling:** Your Coinlayer access key is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or query strings.
- **Discovery method:** Agents search Jentic by intent such as 'convert BTC to USD' or 'get live crypto rates', and Jentic returns the matching Coinlayer operation with its input schema so the agent calls the right endpoint without browsing the reference docs.

## Related APIs

- **CoinGecko API** — Broader free crypto data with deeper coin and DeFi coverage
- **CoinCap API** — Free crypto pricing with simple ranking and history endpoints
- **CoinMarketCap API** — Authoritative rankings and market cap data alongside pricing

## FAQ

### What authentication does the Coinlayer API use?

Coinlayer uses an API access key sent as the access_key query parameter on every request. Through Jentic, the key is stored in the encrypted vault and the agent receives a scoped execution token rather than the raw access_key.

### Can I get historical crypto exchange rates with Coinlayer?

Yes. GET /historical accepts a date in YYYY-MM-DD format and one or more symbols, returning the rates for that date. For a continuous range, use GET /timeframe with start_date and end_date instead.

### What are the rate limits for the Coinlayer API?

Coinlayer's monthly request quota and feature access depend on the plan tier (Free, Basic, Professional, Enterprise). The OpenAPI spec does not declare per-endpoint rate limits - see the Coinlayer pricing page for the cap on your tier.

### How do I convert crypto to fiat through Jentic?

Install the SDK with pip install jentic, search Jentic for convert cryptocurrency to fiat, load the schema for GET /convert, and execute with the from, to, and amount parameters.

### Is the live endpoint available on the free Coinlayer plan?

Yes - the /live endpoint is available on the free tier, while /historical, /timeframe, /change, and /convert are typically reserved for paid tiers. Confirm against your active plan in the Coinlayer dashboard.

### Which currencies can I use as targets for conversion?

Call GET /list to retrieve the full set of supported coins and target currencies (fiat and crypto). The same target codes can then be passed to /live, /historical, /timeframe, and /convert.

### Can I limit what my agent is allowed to do with the Coinlayer API?

Yes. Because you self-host Jentic One, your own rules decide which Coinlayer operations and credentials the agent may use, and the Coinlayer API is read-only exchange-rate lookups to begin with. You can allow only the operations the agent needs, such as fetching live rates with GET /live or converting between coins with GET /convert, while leaving out calls like GET /timeframe history or GET /change unless you choose to add them. The agent can call only the endpoints you have granted.