Salesforce APIs

"The Salesforce API" isn't one thing — it's a family of APIs, each built for a different job. Picking the wrong one is a common source of slow, fragile integrations.

The main APIs at a glance

API	Best for	Notes
REST API	General-purpose CRUD on records, simple and widely supported	JSON over HTTP; the default choice for most new integrations
SOAP API	Legacy systems or strict enterprise standards requiring WSDL/XML	Heavier payloads; still common in older enterprise middleware
Bulk API 2.0	Loading or exporting large volumes of records (thousands to millions)	Asynchronous, chunked, designed to avoid timeouts and limit exhaustion
Streaming API / Pub-Sub API	Subscribing to a continuous stream of events or changes	Underpins Platform Events and Change Data Capture (CDC)
Metadata API / Tooling API	Deploying or inspecting org configuration (fields, objects, Apex)	Used by CI/CD tools and IDEs, not typically by day-to-day business integrations

Choosing between REST, SOAP, and Bulk

In practice: default to REST API unless something specific pulls you elsewhere — either a legacy SOAP requirement on the other side, or a data volume that REST wasn't designed for.

A quick REST API example

Reading an Account by Id with the REST API:

GET /services/data/v61.0/sobjects/Account/001XXXXXXXXXXXXXXX
Authorization: Bearer <access_token>

Creating one:

POST /services/data/v61.0/sobjects/Account
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "Name": "Acme Robotics",
  "Industry": "Manufacturing"
}

Every call needs a valid access token — see Authentication for how to get one safely.

Why Bulk API exists

The REST API processes one record (or a small composite batch) per request, which is fine for interactive use but inefficient — and limit-expensive — for loading 500,000 rows. Bulk API 2.0 instead:

1. Accepts a CSV (or JSON) upload describing the job.
2. Processes it asynchronously in chunks on Salesforce's servers.
3. Lets you poll for job status and download success/failure results separately.

This trades immediacy for throughput and resilience against timeouts.

Common mistakes

• Using REST API in a tight loop for bulk loads. Thousands of sequential REST calls will hit API request limits and run slowly; Bulk API 2.0 exists for exactly this case.
• Choosing SOAP "because it feels more enterprise." Unless you have an explicit requirement to match a SOAP contract, REST is simpler, lighter, and better supported by modern tooling.
• Not versioning API calls deliberately. Pin a specific API version (e.g. v61.0) in production integrations so a future Salesforce release doesn't silently change behavior under you.
• Confusing Streaming/Pub-Sub API with polling. These APIs push events to subscribers; if your integration is still polling on a timer, you're not using them as intended — see Platform Events and CDC.

Learn more on Trailhead

Platform API Basics covers REST, SOAP, Bulk 2.0, and the Pub/Sub API with guided practice.

Quiz

Check your understanding

Question 1 of 5

You need to load 800,000 new Lead records overnight into Salesforce. Which API is purpose-built for this?