---
title: "Rust Exchange Rate API"
description: "Integrate exchange rates into Rust apps with the official AllRatesToday SDK. cargo add allratestoday to get started with 160+ currencies."
canonical: https://allratestoday.com/docs/rust-exchange-rate-api/
source: AllRatesToday (https://allratestoday.com/) — Markdown mirror of the page above; index of all pages at https://allratestoday.com/llms.txt
generated: 2026-10-10T18:37:54.413Z
---

# Rust Exchange Rate API | AllRatesToday Rust SDK

Integrate exchange rates into Rust apps with the official AllRatesToday SDK. cargo add allratestoday to get started with 160+ currencies.

  **Documentation index:** see the [full API reference](https://allratestoday.com/docs/) for all REST endpoints. For other SDKs, visit [the docs hub](https://allratestoday.com/docs/).

# Rust Exchange Rate API — AllRatesToday SDK

The [`allratestoday`](https://crates.io/crates/allratestoday) crate is the official Rust SDK for the AllRatesToday currency API. It provides a typed, async client for fetching live mid-market rates, converting between 160+ currencies, querying historical time-series, and more — all with idiomatic Rust error handling.

The crate is published on [crates.io](https://crates.io/crates/allratestoday) and full API documentation is available on [docs.rs](https://docs.rs/allratestoday). Source code and issue tracking live on [GitHub](https://github.com/AllRates-Today/allratestoday-rust).

## Installation

Add the crate with Cargo:

```
cargo add allratestoday
```

Or add it directly to your `Cargo.toml`:

```
[dependencies]
allratestoday = "0.1"
```

The crate uses `reqwest` under the hood and requires an async runtime such as `tokio`.

## Quick Start

Create a client, fetch the latest rates, and convert a currency amount in a few lines:

```
use allratestoday::AllRatesToday;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = AllRatesToday::new("art_live_xxxxx");

    // Get latest rates for USD against EUR and GBP
    let rates = client.latest("USD", Some(&["EUR", "GBP"])).await?;
    println!("{:#?}", rates);

    // Convert 100 USD to EUR
    let result = client.convert("USD", "EUR", 100.0).await?;
    println!("100 USD = {} EUR", result.result);

    Ok(())
}
```

## Authentication

Every request is authenticated with a Bearer token derived from your API key. Pass the key when constructing the client:

```
let client = AllRatesToday::new("art_live_xxxxx");
```

1. Sign up at [allratestoday.com/register](https://allratestoday.com/register).
2. Verify your email.
3. Copy the key from your [dashboard](https://allratestoday.com/profile). It begins with `art_live_`.
4. Pass it to `AllRatesToday::new()` or load it from an environment variable at runtime.

For production apps, avoid hardcoding the key. Load it from an environment variable instead:

```
let api_key = std::env::var("ALLRATES_API_KEY")
    .expect("ALLRATES_API_KEY must be set");
let client = AllRatesToday::new(&api_key);
```

## All Methods

The `AllRatesToday` struct exposes the following async methods. All return a `Result` with structured response types and `AllRatesTodayError` on failure.

### `latest(base, symbols)`

Fetch the latest exchange rates for a base currency, optionally filtered to specific target symbols.

```
// All rates from USD
let all = client.latest("USD", None).await?;

// Only EUR and GBP
let filtered = client.latest("USD", Some(&["EUR", "GBP"])).await?;
```

| Parameter | Type | Description |
| --- | --- | --- |
| `base` | `&str` | Base currency code (e.g. `"USD"`). |
| `symbols` | `Option<&[&str]>` | Optional list of target currency codes. Pass `None` for all. |

### `convert(from, to, amount)`

Convert an amount from one currency to another using the latest mid-market rate.

```
let result = client.convert("EUR", "JPY", 250.0).await?;
println!("{} EUR = {} JPY", result.query.amount, result.result);
```

| Parameter | Type | Description |
| --- | --- | --- |
| `from` | `&str` | Source currency code. |
| `to` | `&str` | Target currency code. |
| `amount` | `f64` | Amount to convert. |

### `for_date(date, base, symbols)`

Retrieve historical exchange rates for a specific date.

```
let historical = client.for_date("2025-01-15", "USD", Some(&["EUR", "GBP"])).await?;
println!("{:#?}", historical);
```

| Parameter | Type | Description |
| --- | --- | --- |
| `date` | `&str` | Date in `YYYY-MM-DD` format. |
| `base` | `&str` | Base currency code. |
| `symbols` | `Option<&[&str]>` | Optional list of target currency codes. |

### `time_series(start, end, base, symbols)`

Fetch exchange rates over a date range. Returns a map of dates to rate objects.

```
let series = client.time_series(
    "2025-01-01",
    "2025-01-31",
    "USD",
    Some(&["EUR", "GBP"]),
).await?;

for (date, rates) in &series.rates {
    println!("{}: {:#?}", date, rates);
}
```

| Parameter | Type | Description |
| --- | --- | --- |
| `start` | `&str` | Start date (`YYYY-MM-DD`). |
| `end` | `&str` | End date (`YYYY-MM-DD`). |
| `base` | `&str` | Base currency code. |
| `symbols` | `Option<&[&str]>` | Optional list of target currency codes. |

### `symbols()`

List all supported currencies with their names and codes.

```
let currencies = client.symbols().await?;
for (code, info) in &currencies.symbols {
    println!("{}: {}", code, info.name);
}
```

Takes no parameters. Returns a map of currency codes to metadata objects.

### `get_rate(from, to)`

Get the current exchange rate for a single currency pair.

```
let rate = client.get_rate("GBP", "USD").await?;
println!("1 GBP = {} USD", rate.rate);
```

| Parameter | Type | Description |
| --- | --- | --- |
| `from` | `&str` | Source currency code. |
| `to` | `&str` | Target currency code. |

### `get_historical_rates(source, target, period)`

Retrieve historical rates for a currency pair over a preset time period.

```
let history = client.get_historical_rates("USD", "EUR", "30d").await?;
for point in &history.rates {
    println!("{}: {}", point.date, point.rate);
}
```

| Parameter | Type | Description |
| --- | --- | --- |
| `source` | `&str` | Source currency code. |
| `target` | `&str` | Target currency code. |
| `period` | `&str` | Time window: `"1d"`, `"7d"`, `"30d"`, or `"1y"`. |

## Error Handling

All methods return `Result<T, AllRatesTodayError>`. The error enum covers network failures, authentication problems, and API-level errors:

```
use allratestoday::{AllRatesToday, AllRatesTodayError};

match client.latest("USD", None).await {
    Ok(rates) => println!("{:#?}", rates),
    Err(AllRatesTodayError::Unauthorized) => {
        eprintln!("Invalid API key. Check your art_live_ token.");
    }
    Err(AllRatesTodayError::RateLimited) => {
        eprintln!("Rate limit exceeded. Wait or upgrade your plan.");
    }
    Err(AllRatesTodayError::BadRequest(msg)) => {
        eprintln!("Bad request: {}", msg);
    }
    Err(AllRatesTodayError::Network(e)) => {
        eprintln!("Network error: {}", e);
    }
    Err(e) => {
        eprintln!("Unexpected error: {}", e);
    }
}
```

| Variant | Cause |
| --- | --- |
| `Unauthorized` | Missing or invalid API key (HTTP 401). |
| `RateLimited` | Monthly quota exceeded (HTTP 429). Upgrade at [allratestoday.com/pricing](https://allratestoday.com/pricing). |
| `BadRequest(String)` | Invalid parameters — unsupported currency code, bad date format, etc. |
| `Network(reqwest::Error)` | Connection timeout, DNS failure, or other transport-level error. |

## Configuration

By default, the client connects to `https://allratestoday.com`. You can override the base URL for staging or self-hosted deployments:

```
let client = AllRatesToday::new("art_live_xxxxx")
    .base_url("https://staging.allratestoday.com");
```

| Option | Default | Purpose |
| --- | --- | --- |
| `new(api_key)` | — | Create a client with the given API key (Bearer token). |
| `.base_url(url)` | `https://allratestoday.com` | Override the API host. Useful for staging or local development. |

## Full Example

A complete program that fetches the latest rates, converts a value, and checks historical data:

```
use allratestoday::AllRatesToday;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let api_key = std::env::var("ALLRATES_API_KEY")
        .expect("Set ALLRATES_API_KEY environment variable");
    let client = AllRatesToday::new(&api_key);

    // Latest rates
    let latest = client.latest("USD", Some(&["EUR", "GBP", "JPY"])).await?;
    println!("Latest USD rates: {:#?}", latest);

    // Currency conversion
    let conversion = client.convert("USD", "EUR", 1000.0).await?;
    println!("1000 USD = {} EUR", conversion.result);

    // Historical rate for a specific date
    let historical = client.for_date("2025-06-01", "EUR", Some(&["USD"])).await?;
    println!("EUR/USD on 2025-06-01: {:#?}", historical);

    // Time series over a month
    let series = client.time_series(
        "2025-01-01", "2025-01-31", "GBP", Some(&["USD"])
    ).await?;
    println!("GBP/USD January 2025: {} data points", series.rates.len());

    // Single pair rate
    let rate = client.get_rate("AUD", "CAD").await?;
    println!("AUD/CAD: {}", rate.rate);

    // List all supported currencies
    let symbols = client.symbols().await?;
    println!("Supported currencies: {}", symbols.symbols.len());

    // Historical rates with preset period
    let history = client.get_historical_rates("USD", "JPY", "7d").await?;
    println!("USD/JPY last 7 days: {} points", history.rates.len());

    Ok(())
}
```

## Support

- **Bug reports and feature requests:** [GitHub Issues](https://github.com/AllRates-Today/allratestoday-rust/issues)
- **General API support:** [support@allratestoday.com](mailto:support@allratestoday.com)
- **Status page:** [allratestoday.com/status](https://allratestoday.com/status)

## Resources

- **Source code and issues:** [github.com/AllRates-Today/allratestoday-rust](https://github.com/AllRates-Today/allratestoday-rust)
- **crates.io:** [`allratestoday`](https://crates.io/crates/allratestoday)
- **docs.rs:** [`allratestoday` API docs](https://docs.rs/allratestoday)
- **Full API reference:** [/docs/](https://allratestoday.com/docs/)
- **MCP Server:** [/docs/mcp-server/](https://allratestoday.com/docs/mcp-server/)

## Ready to add live FX data to your Rust app?

One `cargo add`. Free tier. No credit card.

 [Get a free API key](https://allratestoday.com/register) [View source on GitHub](https://github.com/AllRates-Today/allratestoday-rust)