twineconvert

free · in-browser · no upload

HCL to JSON
Converter

Drop your HCL file. We'll convert it to JSON right here in your browser, your file never leaves your device.

or drop your file

Select your file here to get started

or drop your file here.

Accepts .hcl, .tf, .tfvars

nothing uploaded no file size cap no signup

How it works

Three steps. No upload, no signup.

  1. 1

    Drop your file

    Click the dropzone above or drag a HCL from your desktop. Files of any size, there's no upload, so there's no upload limit.

  2. 2

    Convert in your browser

    The conversion runs entirely in this tab using JavaScript and WebAssembly. Your file never touches our servers, we don't have any.

  3. 3

    Download

    Get your JSON the moment the conversion finishes. Convert another, or close the tab.

Files stay on your device

Your file is never uploaded. The entire conversion runs in your browser using WebAssembly. We can't see what you convert because we have no server to see it.

No file size limit

Server converters cap free users at 1-2 GB and gate larger files behind a paid plan. Since nothing uploads, our limit is whatever your browser can handle.

Free, no signup, no ads on conversions

No account required. No watermark on the output. No queue. Drop a file, get a converted file.

Formats involved

About HCL and JSON

HCL, HashiCorp Configuration Language

HCL is the config language behind Terraform, Packer, Vault, Consul, and Nomad — all HashiCorp tools. Designed to be more concise than JSON and more human-friendly than YAML. Blocks describe resources (`resource "aws_s3_bucket" "example" { ... }`), attributes use `=`. HCL2 (current) supports expressions, conditionals, and string interpolation.

How to open

Terraform Language Server (in VS Code, IntelliJ, Vim) provides syntax highlighting + validation. `terraform fmt` reformats. Files use `.tf`, `.hcl`, or `.tfvars` extensions.

Full HCL format guide →
JSON, JavaScript Object Notation

JSON is a lightweight text format for structured data, nested objects, arrays, strings, numbers, booleans. It's the lingua franca of web APIs, configuration files, and data interchange between programs. Human-readable when formatted, machine-parseable in every programming language, and roughly half the size of equivalent XML.

How to open

Any text editor reads JSON. Browsers display .json files in a formatted tree view. VS Code and similar editors highlight syntax.

Full JSON format guide →

Related tools

Convert other files to JSON

FAQ

Common questions

Is this HCL → JSON converter really free?

Yes. No signup, no watermark, no daily file count limit. Every conversion runs in your browser, your file never touches our servers because there are no servers.

Where does my file go when I convert it?

Nowhere. The conversion runs entirely in your browser using JavaScript and WebAssembly. Your file is never uploaded to our servers. We don't have any servers handling files, there's nothing for us to log, store, or accidentally leak.

What's the maximum file size?

Whatever your browser can hold in memory. Practically, this means a few hundred MB on most computers, significantly larger than the 1-2 GB caps that server-upload converters charge for. Very large files (multi-GB) may require closing other browser tabs first.

Why convert HCL to JSON?

Infrastructure-as-code config for Terraform and HashiCorp tools. API responses, configuration files, structured data interchange. The most common reason to convert is compatibility, JSON works in places where HCL doesn't, or vice versa.

How do I open a HCL file in the first place?

Terraform Language Server (in VS Code, IntelliJ, Vim) provides syntax highlighting + validation. `terraform fmt` reformats. Files use `.tf`, `.hcl`, or `.tfvars` extensions.

Does this work offline?

Once the page is loaded, the conversion itself runs entirely offline. The first time you use a tool, your browser downloads the conversion library (a one-time cache). If you reload while offline, the page won't load, but you can install the site as a Progressive Web App for full offline use.

Can I convert multiple files at once?

Single file at a time for now. Batch conversion is on the roadmap, for now, drop one file, download the result, then convert the next.