JSON Schema Generator
Instantly generate standard validation Draft-07 JSON Schema documents from raw JSON objects. Supports recursive scanning, required element selectors, and runs completely locally for absolute privacy.
This static pre-rendered block shows how sample data payloads map to structured draft validation matrices:
JSON Sample Payload:
{
"id": 104,
"role": "admin"
}
Compiled Validation Schema:
{
"$schema": "http://json-schema.org/draft-07/schema#",
"type": "object",
"properties": {
"id": { "type": "integer" },
"role": { "type": "string" }
},
"required": ["id", "role"]
} Quickly convert sample client request payloads into strict contracts for API gateways, blocking malformed packets before they run.
Generate standard validation schema blocks to feed developer portals, detailing expected fields and object nesting formats.
Audit payload schemas inside CI/CD regression systems, guaranteeing that microservices output valid structures during upgrades.
Why Use JSON Schemas?
JSON has become the universal standard format to exchange payloads between modern APIs, databases, and microservices. However, since JSON lacks structure rules natively, servers must validate data before committing changes.
By building standard Draft-07 schemas, developers validate object attributes, types, and required formats automatically at the gateway level.
Configuration Parameters
- Mark keys required: Scans sibling parameters inside objects and lists all parameter keys as mandatory required properties.
- Restrict other properties: Sets
"additionalProperties": false, preventing clients from submitting extra, unvalidated keys. - Generate descriptors: Adds custom title and placeholder
"description"properties matching individual keys to aid documentation mapping.
Frequently Asked Questions
What is a JSON Schema and how does it secure API structures? +
JSON Schema is a highly structured, declarative metadata language designed to annotate, validate, and document JSON documents. By declaring strict schemas, engineering teams establish rigid validation contracts outlining acceptable key names, nested parent-child parameters, value datatypes (such as integer vs boolean), character bounds, and mandatory vs optional objects. Validating API requests against these schemas blocks malformed inputs before they run, preventing system crashes and data injection exploits.
Which specific JSON Schema draft versions does this visual builder generate? +
This browser utility generates fully valid schemas matching the industry-standard Draft-07 specification (`http://json-schema.org/draft-07/schema#`). Draft-07 is universally supported across modern programming ecosystems and enterprise validation libraries—including AJV in Node.js, Newtonsoft.Json or System.Text.Json in C#, jsonschema in Python, and raw Jackson validation layers in Java, ensuring seamless integration.
How does the recursive parser compile nested parent objects and child arrays? +
Our compiler parses your raw JSON structure recursively. When the scanner encounters a key mapping to a nested child object, it nests a new `properties` block declaring an `object` node. If a key holds an array, the parser analyzes the first item in the list, extracting its structural type coordinates to declare the correct `items` rules. This allows complex structures to be fully modeled in seconds.
Are my proprietary JSON payloads processed on external servers? +
Absolutely not. Data privacy is our structural baseline. The entire FlowStack JSON Schema Generator executes 100% locally in your browser memory sandbox using vanilla JavaScript. No text inputs, object keys, or structural definitions are ever transmitted across networks to FlowStack servers or tracked by third-party tracking libraries. This makes it completely safe for highly sensitive enterprise logs.
How does the "Mark keys required" check affect API validations? +
Selecting the "Mark keys required" checkbox collects all top-level and nested parameter keys discovered inside an object node and lists them under a strict `required` schema array. When active, validation engines will reject any incoming payload that lacks even a single one of these declared keys, ensuring complete data consistency across integrations.
What is the purpose of setting "additionalProperties: false" inside the options? +
Setting `additionalProperties: false` explicitly blocks clients from submitting any keys that are not specifically defined in your schema properties block. By default, JSON Schema allows extra parameters to pass through unvalidated. Locking this option ensures absolute structural integrity and prevents attackers from injecting unvalidated properties into your databases.
How do I validate if the compiled schema correctly validates my JSON files? +
Once you copy the visual output using our export button, you can paste it along with your JSON documents into a schema validator. This will confirm that your schema is 100% correct, giving you a valid specification sheet for your technical documentations and api gateways.