What are the 5 methods of API?

What are the 5 Methods of API? (GET, POST, PUT, PATCH, DELETE)

The 5 primary API methods are GET, POST, PUT, PATCH, and DELETE. These standard HTTP verbs allow software systems to communicate by performing specific actions on data. Choosing the correct method is critical for maintaining data integrity, as it determines whether an operation is safe to cache or retry following a network failure. Knowing what are the 5 methods of API is fundamental for any developer building modern web applications.

Understanding the 5 Core Methods of API

In the world of web development, APIs act as the essential bridge between different software systems, allowing them to communicate and exchange data seamlessly. The most widely used architecture today, REST (Representational State Transfer), relies on five primary methods to handle these interactions: GET, POST, PUT, PATCH, and DELETE. These methods correspond directly to the CRUD operations in REST API - Create, Read, Update, and Delete - that form the foundation of almost every digital application we use.

As of early 2026, REST remains the dominant choice for public-facing interfaces, with an adoption rate of 89% among developers. While newer alternatives like GraphQL and gRPC are growing in niche environments, the standard HTTP verbs for web services used in RESTful APIs provide a universal language that is easily understood by browsers, servers, and mobile devices alike.

Understanding which method to use for a specific task is not just a matter of following rules - it is about building systems that are reliable, cacheable, and efficient. I remember my first project where I used POST for every single action because it felt simpler. I quickly realized that ignoring these standard methods made debugging impossible and broke basic browser features like the back button and caching.

GET Method: Retrieving Data Without Side Effects

The GET method is the most frequently used operation in web traffic. Its primary purpose is to retrieve information from a server without modifying it. When you type a URL into your browser or click a link, you are essentially triggering a GET request. Because it is a read-only operation, it is classified as a safe method - meaning it does not change the state of the resource on the server.

One of the biggest advantages of GET is its ability to be cached by browsers and Content Delivery Networks (CDNs). This is critical for performance, as top-tier public APIs in 2026 target a latency of around 210ms or less. By caching GET responses, servers can deliver data to users almost instantly without re-processing the request. It is a read-only request. However, there is a strict limit on how much data you can send with a GET request since all parameters must be included in the URL string. This makes it unsuitable for sending sensitive information like passwords or large payloads.

POST Method: Creating New Resources

When you need to send data to a server to create a new resource, POST is the standard choice. Whether you are signing up for a new account, uploading a photo, or submitting a contact form, the POST method handles the heavy lifting of data transmission. Unlike GET, POST requests include data in the request body, which allows for much larger and more complex data structures.

It is important to understand that POST is neither safe nor idempotent. This means that if you send the same POST request multiple times - perhaps by clicking a submit button twice - the server will likely create multiple identical resources. This is why browsers often show a warning if you try to refresh a page after submitting a form. In modern microservices architectures, POST is often the entry point for complex workflows, but its lack of idempotency requires careful handling to prevent duplicate entries in a database.

PUT vs. PATCH: Mastering the Update Process

Rarely does a simple HTTP verb cause as much debate as the difference between PUT and PATCH. Both are used to update existing data, but they operate with completely different philosophies. PUT is designed for a full replacement of a resource. If you want to update a user profile with PUT, you must send the entire user object - including fields that have not changed. If you omit a field, many server implementations will treat it as a command to delete that field or set it to null.

PATCH, on the other hand, is used for partial updates. It only sends the specific fields that need to change. This is significantly more efficient for large resources. For example, if you are updating a single email address in a massive user profile, using PATCH can reduce the data payload size by up to 80% compared to a full PUT request.

I once spent six hours debugging why a resource was losing its metadata every time I updated a title, only to realize I was using PUT with an incomplete object. Efficiency is key. While PUT is inherently idempotent, when to use PUT vs PATCH in API can be more complex to implement correctly because the server must logically merge the new data with the old.

DELETE Method: Removing Resources Safely

As the name suggests, the DELETE method is used to remove a specific resource from the server. Like PUT, DELETE is idempotent. If you delete a specific user ID once, the user is gone. If you call the same DELETE request again, the result is the same - the user remains gone. While the first request might return a success code (200 OK or 204 No Content) and subsequent requests might return a 404 Not Found, the actual state of the server does not change after the first successful call.

Safety first. In production environments, many developers prefer soft deletes - where a record is marked as inactive rather than physically removed from the database - but from the API consumers perspective, the resource is no longer accessible via that URI. Given that 36% of API failures in 2026 are attributed to network connectivity issues, having an idempotent DELETE method is vital. It allows client applications to safely retry the request if a network timeout occurs without worrying about causing unintended side effects on the server.

Why Idempotency and Safety Matter for API Reliability

The concepts of safety and idempotency are the unsung heroes of API design. A method is safe if it does not change the resource state (like GET). A method is idempotent if performing the operation multiple times has the same effect as doing it once (like GET, PUT, and DELETE). This distinction is critical because network connections are often unstable. If a client sends a request and the connection drops before a response is received, the client does not know if the request succeeded. To further your knowledge, you can see REST API methods explained in more detail through official documentation.

If the method used was idempotent, the client can simply resend the request. But if the method was POST, a retry could lead to duplicate data or unexpected errors. Lets be honest, many developers overlook these nuances until they face a production crisis with duplicate payments or corrupted data. By strictly adhering to the proper use of 5 most common API methods, you ensure that your API behaves predictably even when the underlying network does not. Mastering what are the 5 methods of API will make you a much more effective backend engineer.

Comparison of the 5 Main API Methods

GET

• Yes - Does not modify server state

• No body - Data is passed via URL parameters

• Read - Retrieves an existing resource

• Yes - Multiple calls result in the same state

POST

• No - Changes the server state

• Yes - Data is sent in the request body

• Create - Adds a new resource to a collection

• No - Multiple calls create multiple resources

PUT

• No - Modifies server state

• Yes - Requires the full resource representation

• Update - Replaces an entire resource

• Yes - Overwriting with the same data yields the same result

PATCH

• No - Modifies server state

• Yes - Only sends the fields to be changed

• Update - Modifies specific parts of a resource

• Usually No - Depends on implementation (e.g., counters)

DELETE

• No - Modifies server state

• Optional - Usually no body needed

• Delete - Removes a specific resource

• Yes - Deleting a non-existent item is still a deletion

Alex's API Update Nightmare: The PUT vs PATCH Lesson

Alex, a junior developer at a tech startup in San Francisco, was tasked with updating the company's inventory API. He used the PUT method for all updates because the documentation he followed suggested it was the standard for editing resources. The system worked fine during local testing with small objects.

When the app launched, users began reporting that their product descriptions were disappearing whenever they updated just the price. Alex realized that his frontend was only sending the 'price' field in the PUT request. Because PUT is a full replacement, the server was wiping out the description and image URLs since they were missing from the payload.

Instead of rewriting the entire frontend to fetch and send every single field for a simple price change, Alex decided to implement the PATCH method on the backend. He realized that for partial updates, PATCH was far more resilient and prevented accidental data loss from incomplete client payloads.

The change reduced the API's update payload size by 65% on average and eliminated the data loss bugs entirely. Alex reported that mobile users experienced much faster update confirmations, proving that choosing the right method is about both safety and performance.