> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/market-replay-docs/reference/authentication.md).

# Authentication

Authenticate Market Replay requests with your username and password.

Market Replay authenticates requests with a `username` and `password`.

Pass both values on every request.

## Required parameters

Every authenticated request includes:

* `username`
* `password`

Example:

```
https://historical.aws.barchart.com/historical/queryminutes.ashx?username=YOUR_USERNAME&password=YOUR_PASSWORD&symbol=AAPL&start=200902030900&end=200902031200
```

## Supported base URLs

Use the historical base URL for ticks, minutes, EOD data, and events:

```
https://historical.aws.barchart.com/historical/
```

Use the futures options base URL for futures options EOD:

```
https://marketreplay.barchart.com/historical/
```

## Authentication pattern by endpoint

Most endpoints use the same pattern:

* `queryticks.ashx`
* `queryminutes.ashx`
* `querynearbyminutes.ashx`
* `queryformtminutes.ashx`
* `queryeod.ashx`
* `queryevents.ashx`
* `queryminutedaterange.ashx`
* `queryeoddaterange.ashx`
* `futuresoptions`
* `futuresoptions/json`

Example with tick data:

```bash
curl "https://historical.aws.barchart.com/historical/queryticks.ashx?username=YOUR_USERNAME&password=YOUR_PASSWORD&symbol=AAPL&maxrecords=10&order=desc"
```

## Security guidance

Treat your credentials like secrets.

* Store them in environment variables
* Never hard-code them in client-side apps
* Never commit them to version control

Example with environment variables:

```bash
curl "https://historical.aws.barchart.com/historical/queryminutes.ashx?username=${BARCHART_USERNAME}&password=${BARCHART_PASSWORD}&symbol=AAPL&maxrecords=10&order=desc"
```

{% hint style="warning" %}
Do not expose credentials in browser-based frontend code. Route requests through your own backend or job runner.
{% endhint %}

## Related

* [Quickstart](/market-replay-docs/getting-started/quickstart.md)
* [Python example](/market-replay-docs/getting-started/python-example.md)
* [JavaScript example](/market-replay-docs/getting-started/javascript-example.md)
* [curl examples](/market-replay-docs/getting-started/curl-examples.md)
* [Query parameter cheat sheet](/market-replay-docs/reference/query-parameter-cheat-sheet.md)
* [Errors and troubleshooting](/market-replay-docs/reference/errors-and-troubleshooting.md)


---

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