Why does detectFormat pick JSON Map not Array?

The payload starts with { and is not an array. If you also have a cookies array (Playwright), that wrapper is unwrapped as an array instead.

Can I export JSON Map from CookieMan on purpose?

Yes — it is the compact name→value dump. You throw away attributes. Do not use it as a backup format.

Is a JSON Map the same as a Cookie header?

Same information content (names and values), different syntax. Both lack domain. Header detection is used when the text is not valid JSON.

JSON Map vs JSON Array Cookie Export

JSON Map vs JSON Array: why maps default to localhost

A JSON Map cookie export is a flat { "name": "value" } object; converting it to JSON Array here will warn that each cookie defaulted to localhost because a map has no domain, path or flags.

Use a map only for quick scripts. Use an array of objects for anything that must be imported into a browser.

JSON map cookiesJSON array vs mapcookie JSON objectlocalhost default domain

1
Paste the map
An object whose values are strings is detected as JSON Map. Nested objects under each key are treated as cookie fields with the key as name.
2
Convert to JSON Array
Read the warnings. Every string value becomes a session cookie on localhost. Edit domains in the output before Import.
3
Import only after domains are real
CookieMan will write whatever domain is in the JSON. Leaving localhost is the usual reason an import “works” and the site still shows logged out.

Paste a JSON map

Output format

Output

Cookies are credentials. Conversion stays in this page — delete the file when you are done.

Defaults applied to every map entry

Field	JSON Map source	After parse
`name` / `value`	object key / string value	Preserved
`domain`	none	`localhost` + warning
`path`	none	`/`
`secure` / `httpOnly`	none	`false`
`sameSite`	none	`unspecified`
`session`	none	`true`
`hostOnly`	none	`true`

The warning text is exact: Cookie "session_id" from map has no domain, defaulted to localhost. That is not a crash. Ignoring it writes useless cookies. See missing domain → localhost.

When map values are objects

If a value is an object, it is passed through the JSON object normaliser with the key as name. Then domain, path and flags inside that object are honoured. A map of full cookie objects is therefore richer than a map of strings — but at that point you should have used a JSON array.

            {
  "session_id": "abc123",
  "theme": "dark"
}

# warns twice, both domains localhost

{
  "session_id": { "value": "abc123", "domain": ".example.com", "secure": true }
}

# one cookie, domain kept

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