Cookie Converter – Netscape to JSON & JSON to Netscape

Cookie converter for Netscape and JSON

Convert Netscape HTTP Cookie File content to JSON, or turn a JSON cookie export into a Netscape-compatible text file. Processing happens locally in your browser.

How to use

1. Leave Auto-detect selected, or choose a conversion direction.
2. Paste cookie content or upload a .txt, .cookies, or .json file.
3. Review the detected format, cookie count, and validation messages.
4. Copy the result or download it as cookies.json or cookies.txt.

Supported input

• Netscape rows with seven tab-separated fields.
• #HttpOnly_ Netscape cookie rows.
• A JSON array of cookie objects.
• A single JSON cookie object.
• A JSON object containing a cookies array.

Required JSON fields are domain and name. Common fields such as value, path, secure, hostOnly, httpOnly, expirationDate, expiration, and expires are recognized.

Netscape field order

domain    includeSubdomains    path    secure    expiration    name    value

The second and fourth fields use TRUE or FALSE. Expiration is a Unix timestamp; 0 represents a session cookie in many tools.

Conversion examples

Netscape to JSON

Input:

.example.com	TRUE	/	TRUE	1735689600	session_id	abc123

Output:

[
  {
    "domain": ".example.com",
    "hostOnly": false,
    "path": "/",
    "secure": true,
    "expirationDate": 1735689600,
    "name": "session_id",
    "value": "abc123"
  }
]

JSON to Netscape

Input:

{"domain":"example.com","name":"theme","value":"dark","path":"/","secure":false}

Output:

example.com	FALSE	/	FALSE	0	theme	dark

Field mapping

Netscape field	JSON field	Notes
Domain	domain	A leading dot commonly includes subdomains.
Include subdomains	hostOnly	The meanings are inverse: Netscape TRUE becomes hostOnly: false.
Path	path	Defaults to / when missing in JSON.
Secure	secure	Only send the cookie over HTTPS when true.
Expiration	expirationDate	expiration and expires are also accepted on JSON input.
Name	name	Required.
Value	value	Empty values are supported.

Compatibility notes

• #HttpOnly_domain rows are preserved as httpOnly: true and restored when converting back.
• Netscape has no standard field for SameSite, priority, partition keys, or browser store IDs. Those fields cannot be represented in Netscape output.
• Session cookies usually use expiration 0; importing behavior can vary between applications.
• Cookie values containing tabs or line breaks cannot be represented safely in the tab-separated Netscape format.
• Always review cookies before importing them into a browser or automation environment.

Common uses

• Prepare a cookie file for command-line tools that accept the Netscape cookie-jar format.
• Convert browser-extension JSON exports for Playwright, Selenium, or test fixtures.
• Inspect cookie domains, paths, expiration values, and security flags in readable JSON.
• Normalize a cookie export before moving it between approved development or testing environments.

Privacy and safety

Cookie data can contain active session credentials. This converter does not upload input or output, but you should still avoid sharing converted files or pasting them into untrusted services. Only import cookies that you own or are authorized to use.

Frequently asked questions

Why was hostOnly reversed?

The second Netscape field means “include subdomains,” while JSON hostOnly means the opposite.

Why did some JSON fields disappear?

Netscape stores only seven core fields. Browser-specific properties such as sameSite have no standard Netscape column.

Does this tool log or upload cookies?

No. Parsing, validation, conversion, and file generation run in the browser.

Why is a line reported as invalid?

Each Netscape cookie row needs seven tab-separated fields, valid TRUE/FALSE flags, and a non-negative integer expiration value.