🧩

JSON to TypeScript

Paste JSON and get TypeScript interfaces, including nested objects and arrays

Note: The types are inferred from this JSON, not a JSON Schema. When array elements have inconsistent structures, a union type is generated, and field names that are not valid identifiers are quoted.

Instructions

JSON 转 TypeScript 接口使用说明



功能简介


拿到一份接口返回的 JSON,要手写 TypeScript 类型很费时间。这个工具直接读 JSON 结构,递归推断出嵌套的 interface。

使用方法


  • 把 JSON 粘贴到输入框,点「填入示例」可以先看一个复杂例子

  • 填好根接口名(默认 Root),选 `interface` 或 `type` 别名

  • 如果字段可能缺失,勾上「字段可选」给每个字段加 `?`

  • 点「生成 TypeScript」,结果按引用顺序输出,子类型在前、根类型在后

  • 点「复制结果」复制走


  • 注意事项


  • 类型是从这一份 JSON 推断出来的:字段为 `null` 时只会得到 `null`,缺字段也看不出来。要更准确请用多份样本或手写补充

  • 数组里元素结构不一致时会生成联合类型,例如 `(A | B)[]`

  • 空数组只能推断出 `unknown[]`,需要你自己补类型

  • 字段名不是合法标识符时会用引号包起来,符合 TypeScript 语法
  • ❓ FAQ

    What if the object types in an array are inconsistent?

    The tool generates one interface for each distinct structure and writes the array element type as a union, for example `(User | Admin)[]`. You can narrow it down after generation based on your actual business logic.

    Why is the type of a null field null?

    Because there is only this one piece of data, it is impossible to tell whether it will be a string or a number later. It is recommended to add all the types that have appeared in real data, or manually change it to `string | null`.

    Does it support generating Go or Java types?

    Currently it only generates TypeScript. If you want to see the structure first, the nested interface names inferred by this tool are not hard to rewrite as structs in other languages.

    📝 Related Articles

    tool-tutorials

    What to Do When Removing Line Breaks from Large Files Causes Lag, Batch Method Comparison

    This article explains the causes of lag in batch removing line breaks from large files and compares three methods, clarifying how to remove line breaks, the difference between deletion and replacing with empty, troubleshooting steps when it does not work, and specific approaches for mobile and API debugging scenarios, helping you choose the right route by file size and avoid repeated retries.

    tool-tutorials

    Can HTML to Markdown Be Used on Mobile? Installation-Free Online Conversion Method

    You can complete HTML to Markdown with a mobile browser without installing any app. This article provides step-by-step operations you can follow directly, and gives troubleshooting order for common issues such as large file failures, API response format corruption, and distorted nested lists in tables, helping you stably obtain structurally correct Markdown text on mobile.

    tool-tutorials

    What Is the Difference Between Image to PDF and Online Conversion Tools? Which Is Safer

    This article compares the differences between local conversion and cloud conversion in privacy, image quality, and controllability, provides complete operating steps for image to PDF, and focuses on answering four high-frequency issues: file compression, mobile installation-free use, conversion failure, and page ordering, helping you choose the right method according to image sensitivity.

    tool-tutorials

    What is the difference between PDF merging and PDF splitting? Which tool should I use?

    After reading this article, you can quickly determine whether to use PDF merging or PDF splitting, master the four-step merging operation, and solve practical questions such as oversized files after merging, mobile operation, file corruption prompts, and browser security.