JSON to Rust Struct Converter

What is JSON to Rust conversion?

Examples

{"id":101,"name":"Ada Lovelace","email":"ada@example.com","active":true,"roles":["admin","user"]}

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Root {
    pub id: i64,
    pub name: String,
    pub email: String,
    pub active: bool,
    pub roles: Vec<String>,
}

{"repo":"serde","owner":{"login":"dtolnay","id":100}}

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Root {
    pub repo: String,
    pub owner: Owner,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Owner {
    pub login: String,
    pub id: i64,
}

{"users":[{"id":1,"nick":"x"},{"id":2}]}

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Root {
    pub users: Vec<User>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct User {
    pub id: i64,
    pub nick: Option<String>,
}

{"login":"octocat","publicRepos":15,"followerCount":9001,"createdAt":"2011-01-25"}

use serde::{Deserialize, Serialize};

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Root {
    pub login: String,
    #[serde(rename = "publicRepos")]
    pub public_repos: i64,
    #[serde(rename = "followerCount")]
    pub follower_count: i64,
    #[serde(rename = "createdAt")]
    pub created_at: String,
}

How to convert JSON to Rust

1. 1

   Paste your JSON

   Drop a JSON object, array, or API response into the input box. Conversion starts instantly.

2. 2

   Tune the output

   Rename the root struct and toggle serde derives, Debug and Clone, or pub visibility to match your crate's style.

3. 3

   Copy or download

   Grab the generated Rust with one click and paste it straight into your project.

Common Use Cases

Typed API clients

Turn a sample REST or GraphQL response into serde structs for a reqwest or similar client without writing deserialization boilerplate by hand.

Config and fixture parsing

Generate structs for JSON config files, test fixtures, or webhook payloads you need to deserialize with serde_json.

Fast prototyping

Paste an unfamiliar payload to instantly see its shape as Rust types — a quick way to explore a new API before wiring it up.

How the conversion works

Structural inference

Each object becomes a named struct; identical shapes are deduplicated so you get one struct, not copies. Arrays of objects are merged key-by-key, and keys absent from some items become Option<T>.

Correct number typing

Integers map to i64, promote to u64 past i64::MAX, and fall back to f64 beyond u64. Floats are detected from the token (1.0, 2e3) so serde deserialization never fails on a float-into-integer mismatch.

Idiomatic, compilable identifiers

Keys become snake_case fields with #[serde(rename)] back to the original key; Rust keywords, duplicate names, and non-identifier keys are sanitized so the output always compiles.

100% client-side

Parsing and generation run in your browser with no network calls, so your data stays private.

Tips for clean Rust structs

Name your root struct

Set a meaningful root name (e.g. User, ApiResponse) instead of the default Root for readable code.

Add serde_json only when needed

serde_json::Value appears for empty or mixed-type arrays and null-only fields. Give those fields a concrete type from a richer sample if you can, or add serde_json to Cargo.toml.

Review Option vs required

Fields are marked Option<T> only when a sample omits them. Paste a representative payload so the tool infers required and optional fields accurately.

Frequently asked questions