Exchange Rates API Python API Docs | dltHub

Build a Exchange Rates API-to-database pipeline in Python using dlt with AI Workbench support for Claude Code, Cursor, and Codex.

Last updated:

Exchange Rates API is a REST API providing real-time and historical foreign exchange rates, currency conversion, time-series and fluctuation data for 170+ currencies. The REST API base URL is https://api.exchangeratesapi.io/v1 and all requests require an API key passed as a query parameter (access_key).

dlt is an open-source Python library that handles authentication, pagination, and schema evolution automatically. dlthub provides AI context files that enable code assistants to generate production-ready pipelines. Install with uv pip install "dlt[workspace]" and start loading Exchange Rates API data in under 10 minutes.


What data can I load from Exchange Rates API?

Here are some of the endpoints you can load from Exchange Rates API:

ResourceEndpointMethodData selectorDescription
latest/latestGETratesReturns latest exchange rates for all or specified symbols for a given base/date (default base EUR).
historical/{date}GETratesHistorical rates for a specified date (YYYY-MM-DD).
timeseries/timeseriesGETratesTime‑series daily rates between start_date and end_date.
convert/convertGETresultConvert amount from one currency to another (response contains "result" with conversion value).
symbols/symbolsGETsymbolsList of supported currency symbols and descriptions.
fluctuation/fluctuationGETratesFluctuation data (change, start_rate, end_rate) between dates.
latest_with_base/latest?base={base}GETratesLatest rates with specified base (note: base parameter availability depends on plan; API defaults to EUR).
use_etag(headers)GETSupports HTTP ETag / If-None-Match for cache validation; 304 Not Modified may be returned.

How do I authenticate with the Exchange Rates API API?

Authentication is via an API access key included as the access_key query parameter on all requests, e.g. ?access_key=YOUR_KEY. ETag caching is supported via standard If-None-Match / If-Modified-Since headers.

1. Get your credentials

  1. Sign up or log in at https://exchangeratesapi.io/ (or via APILayer marketplace).
  2. In the dashboard, navigate to the API Access Key section.
  3. Create a new key or copy the existing one.
  4. Use the copied key as the access_key query parameter in all API calls.

2. Add them to .dlt/secrets.toml

[sources.exchange_rates_api_source] api_key = "your_api_key_here"

dlt reads this automatically at runtime — never hardcode tokens in your pipeline script. For production environments, see setting up credentials with dlt for environment variable and vault-based options.


How do I set up and run the pipeline?

Set up a virtual environment and install dlt:

uv venv && source .venv/bin/activate uv pip install "dlt[workspace]"

1. Install the dlt AI Workbench:

dlt ai init --agent <your-agent> # <agent>: claude | cursor | codex

This installs project rules, a secrets management skill, appropriate ignore files, and configures the dlt MCP server for your agent. Learn more →

2. Install the rest-api-pipeline toolkit:

dlt ai toolkit rest-api-pipeline install

This loads the skills and context about dlt the agent uses to build the pipeline iteratively, efficiently, and safely. The agent uses MCP tools to inspect credentials — it never needs to read your secrets.toml directly. Learn more →

3. Start LLM-assisted coding:

Use /find-source to load data from the Exchange Rates API API into DuckDB.

The rest-api-pipeline toolkit takes over from here — it reads relevant API documentation, presents you with options for which endpoints to load, and follows a structured workflow to scaffold, debug, and validate the pipeline step by step.

4. Run the pipeline:

python exchange_rates_api_pipeline.py

If everything is configured correctly, you'll see output like this:

Pipeline exchange_rates_api_pipeline load step completed in 0.26 seconds 1 load package(s) were loaded to destination duckdb and into dataset exchange_rates_api_data The duckdb destination used duckdb:/exchange_rates_api.duckdb location to store data Load package 1749667187.541553 is LOADED and contains no failed jobs

Inspect your pipeline and data:

dlt pipeline exchange_rates_api_pipeline show

This opens the Pipeline Dashboard where you can verify pipeline state, load metrics, schema (tables, columns, types), and query the loaded data directly.


Python pipeline example

This example loads latest and convert from the Exchange Rates API API into DuckDB. It mirrors the endpoint and data selector configuration from the table above:

import dlt from dlt.sources.rest_api import RESTAPIConfig, rest_api_resources @dlt.source def exchange_rates_api_source(api_key=dlt.secrets.value): config: RESTAPIConfig = { "client": { "base_url": "https://api.exchangeratesapi.io/v1", "auth": { "type": "api_key", "api_key": api_key, }, }, "resources": [ {"name": "latest", "endpoint": {"path": "latest", "data_selector": "rates"}}, {"name": "convert", "endpoint": {"path": "convert", "data_selector": "result"}} ], } yield from rest_api_resources(config) def get_data() -> None: pipeline = dlt.pipeline( pipeline_name="exchange_rates_api_pipeline", destination="duckdb", dataset_name="exchange_rates_api_data", ) load_info = pipeline.run(exchange_rates_api_source()) print(load_info)

To add more endpoints, append entries from the resource table to the "resources" list using the same name, path, and data_selector pattern.


How do I query the loaded data?

Once the pipeline runs, dlt creates one table per resource. You can query with Python or SQL.

Python (pandas DataFrame):

import dlt data = dlt.pipeline("exchange_rates_api_pipeline").dataset() sessions_df = data.latest.df() print(sessions_df.head())

SQL (DuckDB example):

SELECT * FROM exchange_rates_api_data.latest LIMIT 10;

In a marimo or Jupyter notebook:

import dlt data = dlt.pipeline("exchange_rates_api_pipeline").dataset() data.latest.df().head()

See how to explore your data in marimo Notebooks and how to query your data in Python with dataset.


What destinations can I load Exchange Rates API data to?

dlt supports loading into any of these destinations — only the destination parameter changes:

DestinationExample value
DuckDB (local, default)"duckdb"
PostgreSQL"postgres"
BigQuery"bigquery"
Snowflake"snowflake"
Redshift"redshift"
Databricks"databricks"
Filesystem (S3, GCS, Azure)"filesystem"

Change the destination in dlt.pipeline(destination="snowflake") and add credentials in .dlt/secrets.toml. See the full destinations list.


Troubleshooting

Authentication failures

If you receive error code 101 or HTTP 401/403, verify you included a valid access_key query parameter (access_key=YOUR_KEY). Ensure account is active and subscription supports the requested endpoint.

Rate limits and quota exceeded

Error code 104 indicates monthly/API request volume reached. Upgrade your plan or reduce request frequency. Use ETags to reduce calls.

Invalid parameters and date errors

Errors 201/202/301/302 indicate invalid base, symbols or date formats. Ensure dates are YYYY-MM-DD and timeframe for timeseries/fluctuation does not exceed 365 days.

Ensure that the API key is valid to avoid 401 Unauthorized errors. Also, verify endpoint paths and parameters to avoid 404 Not Found errors.


Next steps

Continue your data engineering journey with the other toolkits of the dltHub AI Workbench:

  • data-exploration — Build custom notebooks, charts, and dashboards for deeper analysis with marimo notebooks.
  • dlthub-runtime — Deploy, schedule, and monitor your pipeline in production.
dlt ai toolkit data-exploration install dlt ai toolkit dlthub-runtime install

Was this page helpful?

Community Hub

Need more dlt context for Exchange Rates API?

Request dlt skills, commands, AGENT.md files, and AI-native context.