> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hologram.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Beginner's guide to the Hologram REST API

> Learn about core concepts, authentication, and common endpoints to manage SIMs and devices via the REST API. Use the REST API to automate actions you perform in your dashboard, such as SIM activation, tagging, plan changes, messaging, and monitoring.

<Card title="Hologram REST API" icon="code" href="/api/v1">
  Full API reference for the Hologram REST API.
</Card>

## What is a REST API?

The REST API is a set of HTTP endpoints that let you programmatically manage your fleet. Bulk actions and automation are where it shines.

## Authentication

Include your API key using Basic auth.

```http theme={null}
Authorization: Basic Base64Encode("apikey:YOUR_API_KEY")
```

<Warning>
  **Caution:** Never transmit API keys in plaintext or commit them to source control.
</Warning>

## Anatomy of an endpoint

* Base URL: `https://dashboard.hologram.io/api/1/`
* Categories: `devices`, `links/cellular`, `plans`, `usage`, `sms`, `tunnelkeys`, `organizations`, `users`
* Query params: `orgid`, `limit`, etc.

## Common endpoints

### Get plan information

```http theme={null}
GET https://dashboard.hologram.io/api/1/plans?orgid={ORG_ID}
```

### Activate SIMs in bulk

```http theme={null}
POST https://dashboard.hologram.io/api/1/links/cellular/bulkclaim?orgid={ORG_ID}
```

Body example:

```
{
  "sims": ["{ICCID_1}", "{ICCID_2}"],
  "plan": {PLAN_ID},
  "zone": "{PLAN_ZONE}"
}
```

### Get tags

```http theme={null}
GET https://dashboard.hologram.io/api/1/devices/tags?orgid={ORG_ID}
```

### List devices (get Device ID/Link ID)

```http theme={null}
GET https://dashboard.hologram.io/api/1/devices?orgid={ORG_ID}
```

### Tag SIMs

```http theme={null}
POST https://dashboard.hologram.io/api/1/devices/tags/{TAG_ID}/link?orgid={ORG_ID}
```

Body:

```json theme={null}
{ "deviceids": [DEVICE_ID_1, DEVICE_ID_2] }
```

### Change plans (bulk)

```http theme={null}
POST https://dashboard.hologram.io/api/1/links/cellular/changeplan
```

Body:

```
{
  "linkids": [LINKID_1, LINKID_2],
  "plan": PLAN_ID,
  "tier": "{PLAN_ZONE}",
  "orgid": ORG_ID
}
```

### Pause or resume a SIM

```http theme={null}
POST https://dashboard.hologram.io/api/1/links/cellular/{linkid}/state?orgid={ORG_ID}
```

Body:

```json theme={null}
{ "state": "pause" }
```

## Related actions

<Card title="REST API keys" href="/dashboard/account/rest-api-key" horizontal />

<Card title="Tag multiple SIMs via API" href="/guides/rest-api/tag-multiple-sims-using-the-rest-api" horizontal />