JSON to Rust Struct
Paste JSON and get Rust structs with serde derives. Option<T> for nullable fields and rename attributes. Private, runs in your browser.
Paste JSON on the left. Add a second sample to find optional fields.
JSON input
Stays in your browserRust code
Shortcuts: Ctrl+Enter run · Ctrl+Shift+C copy result · / search (use ⌘ on Mac)
Next steps
Need the same types in another language? JSON to TypeScript, JSON to Go Struct, JSON to C# Class, JSON to Java POJO, JSON to Python Dataclass, JSON to Dart Class. Or validate a document against a JSON Schema.
Free Online JSON to Rust Struct Generator
Generate Rust structs that work with serde_json, with the derives and field names already in place. It gives developers a quick browser-based way to solve a focused json to rust struct task before moving the result into a project.
How to generate Rust code from JSON
Paste a JSON object or an array of objects into the input box and press Generate. Fields are snake_case with a #[serde(rename = "...")] where the JSON key differs, or use rename_all = "camelCase" for the whole struct. Nullable and optional fields become Option<T>.
One input, every language
Your JSON stays in the box when you switch the language tabs, and the code is generated again at once. Each language also has its own page, so you can bookmark the one you use.
How types are worked out
- Whole numbers and numbers with decimals are told apart.
- Add more samples with Add sample: a key missing from some samples becomes optional, and null makes a type nullable.
- Arrays of objects are merged into one type, and nested objects become their own types named after the key.
- Keys that are not valid names in the language (such as first-name or 2fa) are renamed and mapped back, never rejected.
Worked example
The sample JSON in the box above, generated with the default options:
{
"id": 1,
"name": "Ada",
"email": null,
"tags": ["x"],
"address": { "city": "Pune", "pin": "411001" },
"createdAt": "2026-01-15T10:30:00Z"
}use serde::{Deserialize, Serialize};
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct Root {
pub id: i64,
pub name: String,
pub email: Option<String>,
pub tags: Vec<String>,
pub address: Address,
#[serde(rename = "createdAt")]
pub created_at: String,
}
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct Address {
pub city: String,
pub pin: String,
}
Common mistakes
- A single sample cannot show which fields are optional. Paste two or three different responses for a realistic result.
- A value that is always null gives no type information, so it is treated as a nullable string. Change it by hand if it is something else.
- Numbers are typed from the samples: 1 and 1.0 look the same in JSON, so use a sample with decimals where you need a float.