DynamoDB JSON to Standard JSON Converter

What does the DynamoDB JSON to Standard JSON Converter do?

The DynamoDB JSON to Standard JSON Converter & Unmarshaller transforms verbose AWS DynamoDB typed attribute JSON payloads (such as {"S": "user#12"} or {"N": "34"}) into clean, standard JSON objects and arrays. It strips out low-level DynamoDB type descriptors recursively across maps, lists, string sets, and binary values.

Core Concepts

Understanding DynamoDB typed attribute descriptors:

• Attribute Value Wrappers: In DynamoDB APIs, primitive types are wrapped in descriptor keys: "S" (String), "N" (Number), "BOOL" (Boolean), "NULL" (Null), "M" (Map), "L" (List), "SS" (String Set), "NS" (Number Set), and "BS" (Binary Set).
• Recursive Unmarshalling: Traverses deeply nested maps and array collections to restore original object models without loss of precision.
• Batch Processing: Supports unmarshalling individual database items or multi-item array results returned from AWS CLI aws dynamodb scan and query operations.

How to use the tool?

1. Paste DynamoDB JSON: Paste your raw DynamoDB typed JSON payload or batch array into the editor or click Load Sample.
2. Execute Conversion: Click Convert to Standard JSON to recursively unmarshall all typed attribute descriptors.
3. Copy & Export: Click Copy or Download to save your clean standard JSON document.

Related Developer Utilities

If you work with AWS DynamoDB, cloud infrastructure, and JSON formatting, explore these complementary tools:

• Standard JSON to DynamoDB JSON Converter: Convert standard JSON objects into DynamoDB typed attribute format.
• AWS IAM Policy Minifier: Compress IAM policies and resolve 6,144 character quota errors.
• JSON Formatter & Beautifier: Format and prettify messy JSON payloads.
• JSON Syntax Validator: Validate JSON syntax and inspect character offsets.

REST API Integration

Blueutils provides a free REST API endpoint (POST https://blueutils.com/api/aws/dynamodb-to-json) to programmatically convert verbose DynamoDB JSON structures into standard clean JSON payloads.

API Request Parameters

API Request Payload Examples

cURL

curl -X POST https://blueutils.com/api/aws/dynamodb-to-json \
  -H "Content-Type: application/json" \
  -d '{
    "rawText": "{\"pk\": {\"S\": \"user#102\"}, \"age\": {\"N\": \"34\"}}"
  }'

Python

import requests

url = "https://blueutils.com/api/aws/dynamodb-to-json"
payload = { "rawText": '{"pk": {"S": "user#102"}, "age": {"N": "34"}}' }
headers = {"Content-Type": "application/json"}
response = requests.post(url, json=payload, headers=headers)
print(response.json())

Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class Main {
    public static void main(String[] args) throws Exception {
        String jsonPayload = """
            {
                "rawText": "{\\"pk\\": {\\"S\\": \\"user#102\\"}, \\"age\\": {\\"N\\": \\"34\\"}}"
            }
            """;

        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = HttpRequest.newBuilder()
            .uri(URI.create("https://blueutils.com/api/aws/dynamodb-to-json"))
            .header("Content-Type", "application/json")
            .POST(HttpRequest.BodyPublishers.ofString(jsonPayload))
            .build();

        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
        System.out.println(response.body());
    }
}

API Response Parameters

API Response Payload Examples

Success Response (HTTP 200 OK)

{
  "isValid": true,
  "outputText": "{\n  \"pk\": \"user#102\",\n  \"age\": 34\n}"
}

Validation Failure Response (HTTP 400 Bad Request)

{
  "isValid": false,
  "error": "Invalid JSON syntax: Unexpected token in JSON at position 5"
}

Rate Limit Exceeded Response (HTTP 429 Too Many Requests)

{
  "error": "API rate limit exceeded. Please wait or contact support@blueutils.com."
}

Why use an API to convert DynamoDB JSON?

Integrating the DynamoDB JSON to Standard JSON API into data pipelines, ETL workflows, or serverless microservices provides essential benefits:

• Rapid Script Validation: Converts raw AWS DynamoDB scan and query results into standard clean JSON structures before sending to downstream services.
• Optimized Token Efficiency for AI Agents: LLMs consume unnecessary tokens parsing verbose {"S": "..."} type wrappers. Unmarshalling payloads via API strips 40% to 60% of redundant formatting overhead.
• Deterministic Accuracy Without Hallucinations: Ensures 100% accurate type restoration across complex nested maps, lists, numbers, and boolean values.

Native Usage

How to unmarshall DynamoDB JSON locally in terminal environments or scripts:

Windows (CMD / PowerShell)

# Using Node.js AWS SDK unmarshall in PowerShell
node -e "const { unmarshall } = require('@aws-sdk/util-dynamodb'); console.log(JSON.stringify(unmarshall(JSON.parse(process.argv[1])), null, 2))" '{\"pk\": {\"S\": \"user#12\"}}'

Linux / Unix (Bash)

# Using Node.js AWS SDK unmarshall CLI
node -e "const { unmarshall } = require('@aws-sdk/util-dynamodb'); const data = JSON.parse(require('fs').readFileSync('item.json')); console.log(JSON.stringify(unmarshall(data), null, 2));"

Python

Using boto3 in Python:

from boto3.dynamodb.types import TypeDeserializer
import json

deserializer = TypeDeserializer()
dynamodb_item = {"pk": {"S": "user#102"}, "age": {"N": "34"}}
standard_item = {k: deserializer.deserialize(v) for k, v in dynamodb_item.items()}

print(json.dumps(standard_item, indent=2))

Java

Using AWS SDK for Java v2:

import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
import java.util.Map;
import java.util.HashMap;

public class DynamoDbUnmarshallerExample {
    public static void main(String[] args) {
        Map<String, AttributeValue> item = new HashMap<>();
        item.put("pk", AttributeValue.builder().s("user#102").build());
        item.put("age", AttributeValue.builder().n("34").build());

        String pk = item.get("pk").s();
        int age = Integer.parseInt(item.get("age").n());
        System.out.println("Clean record: pk=" + pk + ", age=" + age);
    }
}