Variables

Variables let you write a value once and reuse it in any request. Write {{name}} anywhere in a request and Kitten swaps in the value when it sends it.

Use a Variable

Type {{ in the URL, a header, the body or an auth field to pick from your variables. Variables that will resolve are highlighted. A variable Kitten can't find is shown in red and sent as written; click it to add the variable.

Kitten fills in variables in the URL, query and path parameters, headers, the body, form fields, file paths, GraphQL queries and variables, the proxy URL, and auth fields. The request keeps the {{name}} text, so only the copy that is sent changes.

Scripts don't use this syntax. In a script, read a variable with get_var("name"). See Scripts.

Fallback Values

Add a fallback after a colon. Kitten uses it when the variable isn't set:

{{port:8080}}

If port is set, its value wins.

Where Variables Live

When two places define the same name, the one closest to the request wins:

Disabled rows and rows with no name are skipped.

Environments

An environment is a named set of variables, such as dev or production. Pick one from the environment switcher, or choose No Environment.

A collection environment is saved with its collection, so it's versioned and shared with it. A workspace environment applies to every collection in the workspace.

To read a variable only from the active environment, write {{env.name}}. To read from a specific environment, write {{env.production.name}}.

Secret and Local-Only Variables

Mark a variable as secret with the eye icon to mask its value in the panel.

In a collection that lives in a folder on disk, a variable can be local only. It's saved in a <environment>.local.yml file that git ignores, so it never gets committed. Use it for your own tokens and passwords.

Capture Values From a Response

In the request's Vars tab, the Post side saves values from the response into a variable after each request. Each capture has a name and an expression, such as res.body.token, res.headers.etag or res.status. Choose where to save it: request, folder, environment, collection or global.

Date Templates

Date templates insert dates relative to today, so a request like "last 30 days" never goes stale.

Dates come out as yyyy-mm-dd, and {{now}} as yyyy-mm-dd hh:MM:ss. They use your computer's time zone. Add utc. to use UTC instead, for example {{utc.today}} or {{utc.now}}.

The Postman-style {{$today}} works too.

Formats

Add a format after a colon:

Any other character is kept as-is. There are also three named formats:

Examples

On July 24, 2026 at 13:45:09:

A date template wins over a variable with the same name, so {{today}} is always a date. To read a variable called today, write {{env.today}}.

When you import a cURL command, Kitten turns dates near today into date templates for you. For example, 2026-07-23 becomes {{yesterday}} when you import it on July 24.

Dynamic Variables

Dynamic variables generate a new value every time you send. Kitten supports all the dynamic variables Postman and Bruno share, plus Bruno's {{$randomNanoId}} and {{$randomIPV4}}. Type {{$ to pick one.

Dates and Times

IDs

Numbers and Booleans

People and Places

Images

Finance

Business and Products

Databases and Tech Words

Internet and Files

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