Calculator
What the CORS Header Generator does
CORS Header Generator: generates Status and HTTP headers from Header set. Example: header set CORS gives status Headers ready.
With Header set entered, the CORS Header Generator works out Status and HTTP headers. Adjust anything and the figures re-derive on the spot.
Most people who open the CORS Header Generator are engineers checking an encoding. Pasting a production payload into an unknown web tool is a real risk, which is why this one stays local.
The work is done by JavaScript already loaded in your browser, so your input never crosses the network.
Field definitions, the method, and a worked example from the default values are all set out further down the page.
What do the CORS Header Generator fields mean?
The CORS Header Generator uses 1 input. A filled form means you can test one idea immediately instead of sourcing every input first.
| Field | What to enter | Default |
|---|---|---|
| Header set | choose from CORS | CORS |
How does the CORS Header Generator work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same generated output.
An empty or malformed field stops the calculation rather than being treated as zero.
Worked example
These are the values the CORS Header Generator loads by default, and the result it produces from them. Below is the same computation the tool performs on load, step by step.
| Header set | CORS |
|---|
| Status | Headers ready |
|---|---|
| HTTP headers | Access-Control-Allow-Origin: * Access-Control-Allow-Methods: GET, POST, OPTIONS Access-Control-Allow-Headers… |
How to use it
- Pick a value for Header set: the options are CORS.
- No submit step is needed; the output updates while you edit.
- Look at Status and HTTP headers in the output panel.
- Copy Link when you want to return to this exact configuration; Print when someone needs it on paper.
What this tool does not do
- Processing happens in your browser, so extremely large inputs are bounded by available memory.
- Output follows the common convention for this format; a specific toolchain may have its own house style.
- It handles the common case well and the unusual case literally.
Frequently asked questions
Just Header set. Every box already holds a working value, so the form is usable immediately, without filling anything in first.
With the values loaded when the page opens, status comes out as Headers ready. Adjust any field to see how much the answer depends on it.
No. Your browser is doing the computing, so we could not see the values even if we wanted to.
No charge. Everything on the page is available without signing in.
There is no estimation step. The result is computed, not inferred.