---
title: Authentication
description: 'Use one of the following schemes to authenticate to the InfluxDB 3 Core API: Token authentication Bearer authentication Basic authentication Querystring authentication'
url: https://docs.influxdata.com/influxdb3/core/api/authentication/
estimated_tokens: 2427
product: InfluxDB 3 Core
version: core
---

[Download InfluxDB 3 Core API Spec](/openapi/influxdb3-core-openapi.yml)

Use one of the following schemes to authenticate to the InfluxDB 3 Core API:

-   Token authentication
-   Bearer authentication
-   Basic authentication
-   Querystring authentication

## Basic Authentication

Use the `Authorization` header with the `Basic` scheme to authenticate v1 API requests.

Works with v1 compatibility [`/write`](#operation/PostV1Write) and [`/query`](#operation/GetV1Query) endpoints in InfluxDB 3.

When authenticating requests, InfluxDB 3 checks that the `password` part of the decoded credential is an authorized token and ignores the `username` part of the decoded credential.

### Syntax

```http
Authorization: Basic <base64-encoded [USERNAME]:AUTH_TOKEN>
```

### Example

```bash
curl "http://localhost:8181/write?db=DATABASE_NAME&precision=s" \
  --user "":"AUTH_TOKEN" \
  --header "Content-type: text/plain; charset=utf-8" \
  --data-binary 'home,room=kitchen temp=72 1641024000'
```

Replace the following:

-   **`DATABASE_NAME`**: your InfluxDB 3 Core database
-   **`AUTH_TOKEN`**: an admin token or database token authorized for the database

## Bearer Authentication

Use the OAuth Bearer authentication scheme to provide an authorization token to InfluxDB 3.

Bearer authentication works with all endpoints.

In your API requests, send an `Authorization` header. For the header value, provide the word `Bearer` followed by a space and a database token.

### Syntax

```http
Authorization: Bearer AUTH_TOKEN
```

### Example

```bash
curl http://localhost:8181/api/v3/query_influxql \
  --header "Authorization: Bearer AUTH_TOKEN"
```

## Query String Authentication

Use InfluxDB 1.x API parameters to provide credentials through the query string for v1 API requests.

Querystring authentication works with v1-compatible [`/write`](#operation/PostV1Write) and [`/query`](#operation/GetV1Query) endpoints.

When authenticating requests, InfluxDB 3 checks that the `p` (*password*) query parameter is an authorized token and ignores the `u` (*username*) query parameter.

### Syntax

```http
https://localhost:8181/query/?[u=any]&p=AUTH_TOKEN
https://localhost:8181/write/?[u=any]&p=AUTH_TOKEN
```

### Examples

```bash
curl "http://localhost:8181/write?db=DATABASE_NAME&precision=s&p=AUTH_TOKEN" \
  --header "Content-type: text/plain; charset=utf-8" \
  --data-binary 'home,room=kitchen temp=72 1641024000'
```

Replace the following:

-   **`DATABASE_NAME`**: your InfluxDB 3 Core database
-   **`AUTH_TOKEN`**: an admin token or database token authorized for the database

```bash
#######################################
# Use an InfluxDB 1.x compatible username and password
# to query the InfluxDB v1 HTTP API
#######################################
# Use authentication query parameters:
#   ?p=AUTH_TOKEN
#######################################

curl --get "http://localhost:8181/query" \
  --data-urlencode "p=AUTH_TOKEN" \
  --data-urlencode "db=DATABASE_NAME" \
  --data-urlencode "q=SELECT * FROM MEASUREMENT"
```

Replace the following:

-   **`DATABASE_NAME`**: the database to query
-   **`AUTH_TOKEN`**: a database token with sufficient permissions to the database

## Token Authentication

Use InfluxDB v2 Token authentication to provide an authorization token to InfluxDB 3.

The v2 Token scheme works with v1 and v2 compatibility endpoints in InfluxDB 3.

In your API requests, send an `Authorization` header. For the header value, provide the word `Token` followed by a space and a database token. The word `Token` is case-sensitive.

### Syntax

```http
Authorization: Token AUTH_TOKEN
```

### Example

```sh
########################################################
# Use the Token authentication scheme with /api/v2/write
# to write data.
########################################################

curl --request post "http://localhost:8181/api/v2/write?bucket=DATABASE_NAME&precision=s" \
  --header "Authorization: Token AUTH_TOKEN" \
  --data-binary 'home,room=kitchen temp=72 1463683075'
```

#### Related

-   [Authenticate v1 API requests](/influxdb3/core/guides/api-compatibility/v1/)
-   [Manage tokens](/influxdb3/core/admin/tokens/)