Forge Json

Pick Fields (Free Online Tool)

Keep only a known allowlist of fields and remove everything else

Paste your JSON → Get results instantly (no signup)

⚡ Instant resultsNo signupRuns in your browser
Try examples:

→ Keep only the name and age fields from this data.

{
"name": "Alice",
"age": 30,
"password": "secret123",
"email": "alice@test.com"
}
Output✓
1{
2  "name": "Alice",
3  "age": 30
4}

Love the result?

Use this exact pipeline in your app, backend, or LLM workflow.

No setup needed. Works with curl, Node, Python.

Uses example data. For edited input, copy from the playground.

Read integration guide

Works with:

  • API responses
  • Nested JSON
  • Arrays & objects

Example: input → output

Input / Output
Input
{
  "name": "Alice",
  "age": 30,
  "password": "secret123",
  "email": "alice@test.com"
}
Output
{
  "name": "Alice",
  "age": 30
}

Related tools

Advanced usage (optional)

Pick Fields

v1.0.0
Structure
objectarraydestructive

Description

Pick Fields

Keep only specified fields — remove everything else. The inverse of Remove Fields. Select the exact paths you want to keep, and all other fields are stripped. Parent objects of selected paths are preserved automatically.

How It Works

Select fields using the path picker. Only the selected paths (and their parent containers) survive. Everything else is removed. Works on single objects, arrays of objects, and deeply nested structures.

Configuration

FieldTypeDefaultDescription
Fields to Keeppath-picker[]Select the paths to keep. All other fields will be removed.

Use Cases

Security & Privacy

  • Strip sensitive fields: Keep only name and email, removing password, ssn, and internal fields
  • Public API response: Pick only the fields that should be exposed publicly
  • Audit logging: Extract only relevant fields for audit records

Data Shaping

  • Column selection: Pick specific fields for CSV export or table display
  • Nested extraction: Keep user.name and user.address.city from deeply nested objects
  • Array projection: Pick the same fields from every item in an array

API Response Trimming

  • Bandwidth reduction: Keep only needed fields to reduce response size
  • Schema conformance: Ensure responses match a specific schema by keeping only defined fields
  • Frontend optimization: Pick only the fields the UI actually renders

Configuration

NameTypeDefaultDescription
Fields to Keeppath-picker[]Select the paths to keep. All other fields will be removed. Parent objects of selected paths are preserved automatically.

Examples

AI Prompt
Keep only the name and age fields from this data.
{
"name": "Alice",
"age": 30,
"password": "secret123",
"email": "alice@test.com"
}
Output✓
1{
2  "name": "Alice",
3  "age": 30
4}
Config
Fields to Keep
name, age

API Usage

POST /api/v1/utilities/structure.pick-fields
Example:
curl -X POST https://your-domain.com/api/v1/utilities/structure.pick-fields \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"inputs":{"primary":{"name":"Alice","age":30,"password":"secret123","email":"alice@test.com"}},"config":{"paths":["name","age"]}}'
Response
1{
2  "name": "Alice",
3  "age": 30
4}