What is the difference between PUT and PATCH?

What You'll Learn

PUT method usage
PATCH method usage
When to use each

PUT vs PATCH

Feature	PUT	PATCH
Update type	Full replacement	Partial update
Required data	Complete resource	Only changed fields
Idempotent	Yes	Yes

PUT Example

code.jsJavaScript

// Replace entire user object
PUT /api/users/1
{
  "id": 1,
  "name": "John Updated",
  "email": "john@example.com",
  "age": 30,
  "role": "admin"
}
// All fields required, missing fields become null/default

PATCH Example

code.jsJavaScript

// Update only specific fields
PATCH /api/users/1
{
  "name": "John Updated"
}
// Only name changes, other fields remain unchanged

Node.js Implementation

code.jsJavaScript

// PUT - replace entire resource
app.put('/users/:id', (req, res) => {
  users[req.params.id] = req.body;
  res.json(users[req.params.id]);
});

// PATCH - merge updates
app.patch('/users/:id', (req, res) => {
  users[req.params.id] = { ...users[req.params.id], ...req.body };
  res.json(users[req.params.id]);
});