In this blog, we'll dive into what JSON escape means, why it's necessary, common escape sequences, and how to handle them in different programming languages.
What is JSON?
Before understanding "escaping" in JSON, let's quickly recap what JSON is.
JSON (JavaScript Object Notation) is a lightweight format for storing and transporting data. It's easy to read and write for both humans and machines. Here's a simple JSON object:
{
"name": "Alice",
"age": 30,
"isMember": true
}
It consists of key-value pairs and supports data types like strings, numbers, booleans, arrays, and nested objects.
What is JSON Escaping?
Escaping in JSON means adding a backslash () before certain characters in a string to ensure the JSON remains valid.
Why? Because some characters—like double quotes ("), newlines (n), or backslashes ()—have special meanings in JSON. If you include them directly in a string, the parser might misinterpret them and throw an error.
Example Without Escaping (Invalid JSON)
{
"quote": "He said, "Hello!""
}
This is invalid, because the JSON parser can't tell where the string ends.
Example With Escaping (Valid JSON)
{
"quote": "He said, "Hello!""
}
Here, the double quotes around Hello are escaped using backslashes, making the string valid JSON.
Common JSON Escape Sequences
Here are some of the most commonly used escape sequences in JSON:
| Character | Escaped Version | Meaning |
| " | " | Double quote |
| \ | Backslash | |
| / | / | Forward slash (optional) |
| b | b | Backspace |
| f | f | Form feed |
| n | n | Newline |
| r | r | Carriage return |
| t | t | Tab |
| uXXXX | Unicode escape | Unicode character code |
When Do You Need to Escape in JSON?
You generally need to escape characters in JSON when:
- Embedding strings with quotes or special characters.
- Generating JSON manually in code or text editors.
- Sending data over HTTP or APIs, where invalid JSON can break parsing.
- Handling user input that might contain quotes, slashes, or special characters.
Most modern libraries or frameworks automatically escape JSON for you when converting objects to strings (called serialization). But if you're manually building or modifying JSON, escaping becomes your responsibility.
JSON Escaping in Different Languages
Let’s look at how JSON escaping is handled in some popular programming languages:
JavaScript
JavaScript has built-in support for JSON:
const obj = { message: "He said, "Hi!"" };
const jsonString = JSON.stringify(obj);
console.log(jsonString);
// Output: {"message":"He said, "Hi!""}
JSON.stringify() automatically escapes characters.
Python
In Python, the json module does the escaping for you:
import json
data = { "message": 'He said, "Hi!"' }
json_str = json.dumps(data)
print(json_str)
# Output: {"message": "He said, "Hi!""}
Java
In Java, libraries like Gson or Jackson handle escaping:
import com.google.gson.Gson;
Map<String, String> data = new HashMap<>();
data.put("message", "He said, "Hi!"");
Gson gson = new Gson();
String json = gson.toJson(data);
System.out.println(json);
Escaping vs Encoding
People often confuse escaping with encoding. While both are ways of preparing data for transport, they serve different purposes:
- Escaping: Makes characters safe for use in code or structured formats (like JSON, HTML, SQL).
- Encoding: Converts data into another format (e.g., Base64, URL encoding) for transmission.
Tools for Escaping JSON
If you're unsure how to escape JSON manually, here are a few handy tools:
- https://jsonlint.com: Validates and formats your JSON.
- https://jsonformatter.org/json-escape-unescape: Escapes/unescapes JSON strings.
- Most IDEs and text editors also support JSON validation and escaping.
Conclusion
JSON escape is all about making sure your strings don’t break your JSON structure. While it's often handled automatically by libraries, understanding how it works helps you debug issues, sanitize user input, and write more robust code.
Whenever you’re embedding strings with quotes, backslashes, or special characters into JSON, remember to escape them properly. It keeps your data safe, clean, and parseable.
Read more on- https://keploy.io/blog/community/json-escape-and-unescape