Run in sandbox

JSON to YAML API#

Convert a JSON file to YAML with a single request to POST /v1/convert/json-to-yaml. The conversion is a direct mapping with no restructuring: output is human-readable block-style YAML with the original key order and unicode characters preserved. By default the response is raw YAML bytes; set direct_download=false to receive metadata with a presigned download URL instead.

Endpoint#

POST /v1/convert/json-to-yaml

Content-Type: multipart/form-data

Accepted input: .json files (UTF-8 encoded)

Output format: .yaml (application/x-yaml)

Authentication#

Requires either a private API key or a JWT token from a public key.

X-API-Key: sk_your_private_key

Or:

Authorization: Bearer <jwt_token>

Request Parameters#

Parameter	Type	Required	Default	Description
`file`	file	Yes	--	The `.json` file to convert. Must be UTF-8 encoded.
`output_filename`	`string`	No	Input filename	Custom output filename. The `.yaml` extension is added automatically.
`direct_download`	`boolean`	No	`true`	When `true`, returns raw YAML bytes. When `false`, returns metadata with a presigned download URL.

Conversion Rules#

Direct mapping from JSON to YAML with no restructuring:

{
  "database": {
    "host": "localhost",
    "port": 5432,
    "credentials": {
      "user": "admin",
      "password": "secret"
    }
  },
  "features": ["auth", "logging"]
}

Becomes:

database:
  host: localhost
  port: 5432
  credentials:
    user: admin
    password: secret
features:
- auth
- logging

Output uses block style (multi-line, human-readable), not flow style
Key order is preserved from the original JSON
Unicode characters are preserved as-is

Response#

Direct Download (`direct_download=true`, default)#

HTTP 200 OK
Content-Type: application/x-yaml
Content-Disposition: inline; filename="config_20260405_123456789.yaml"

Metadata Response (`direct_download=false`)#

{
    "presigned_url": "https://spaces.example.com/...",
    "object_key": "env/files/{project_id}/json-to-yaml/config_20260405_123456789.yaml",
    "filename": "config_20260405_123456789.yaml",
    "file_size": 1234,
    "conversion_time_seconds": 0.03
}

Code Examples#

Python#

import requests

with open("config.json", "rb") as f:
    response = requests.post(
        "https://api.enconvert.com/v1/convert/json-to-yaml",
        headers={"X-API-Key": "sk_your_private_key"},
        files={"file": ("config.json", f, "application/json")}
    )

with open("config.yaml", "wb") as out:
    out.write(response.content)

Node.js#

const form = new FormData();
form.append("file", fs.createReadStream("config.json"));

const response = await fetch("https://api.enconvert.com/v1/convert/json-to-yaml", {
    method: "POST",
    headers: { "X-API-Key": "sk_your_private_key" },
    body: form
});

const yaml = await response.text();

PHP#

$ch = curl_init("https://api.enconvert.com/v1/convert/json-to-yaml");
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => ["X-API-Key: sk_your_private_key"],
    CURLOPT_POSTFIELDS => ["file" => new CURLFile("config.json", "application/json")]
]);
$yaml = curl_exec($ch);
curl_close($ch);

Go#

body := &bytes.Buffer{}
writer := multipart.NewWriter(body)
part, _ := writer.CreateFormFile("file", "config.json")
file, _ := os.Open("config.json")
io.Copy(part, file)
writer.Close()

req, _ := http.NewRequest("POST", "https://api.enconvert.com/v1/convert/json-to-yaml", body)
req.Header.Set("Content-Type", writer.FormDataContentType())
req.Header.Set("X-API-Key", "sk_your_private_key")
resp, _ := http.DefaultClient.Do(req)

Error Responses#

Status	Condition
`400 Bad Request`	File is not a `.json` file
`400 Bad Request`	Invalid JSON content
`400 Bad Request`	JSON to YAML conversion failed
`401 Unauthorized`	Missing or invalid API key / JWT token
`402 Payment Required`	Monthly ops allowance exhausted
`413 Payload Too Large`	File exceeds plan's maximum file size

Limits#

Limit	Value
Max file size	Plan-dependent (Founding: 5 MB)
Input encoding	UTF-8 only
Monthly conversions	Plan-dependent

Frequently asked questions#

How do I convert JSON to YAML with a REST API?#

Send a multipart/form-data POST request to /v1/convert/json-to-yaml with your .json file in the file field, authenticated with an X-API-Key header or a JWT Authorization: Bearer token. The response is the converted YAML.

Does the JSON to YAML conversion preserve key order?#

Yes. Key order from the original JSON is preserved, unicode characters are kept as-is, and the structure is mapped directly with no restructuring.

Is the YAML output block style or flow style?#

Output uses block style (multi-line, human-readable YAML) rather than inline flow style, as shown in the conversion example on this page.

Can I get a presigned download URL instead of raw YAML bytes?#

Yes. Set direct_download=false to receive a metadata response with a presigned_url, object_key, filename, file_size, and conversion_time_seconds.

Why does the JSON to YAML API return 400 Bad Request?#

A 400 is returned when the file is not a .json file, the content is not valid JSON, or the conversion fails. Files over your plan's size limit return 413 Payload Too Large.

← xml-to-json yaml-to-json →

API Documentation