New

JSON Schema Generator

Runs in browser

Generate JSON Schema from sample JSON with options for draft version, required fields, descriptions, and additionalProperties. Useful for API validation and LLM tool-call schemas.

JSON Schema Generator tool

Schema version
Required fields
Additional properties
Add descriptions
1
2
3
4
5
6
7
8
9
10
11
12
13
14
JSON Schema
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61

How to use

  1. Paste JSON sample

    Load your object manually or upload a .json file.

  2. Set schema options

    Choose draft version, required strategy, descriptions, and additionalProperties behavior.

  3. Copy or download

    Copy generated schema or download as .json for validators and OpenAPI specs.

Examples

  • User profile

    Nested object with arrays.

    Input
    {...}
    Output
    { "type": "object", ... }

Frequently asked questions

How are array item schemas inferred?
The generator inspects the first non-null item as a representative sample.
Can I use this for production contracts?
Yes, but treat generated output as a starting point and review constraints manually.

Related tools

You might find these useful too.