Calculator
What the Cron Expression Parser does
Cron Expression Parser: calculates Status and Fields JSON from Cron expression. Example: cron expression 0 9 * * 1-5 gives status Parsed fields.
Give the Cron Expression Parser your Cron expression and it works out Status and Fields JSON. Adjust anything and the figures re-derive on the spot.
Most people who open the Cron Expression Parser 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.
Payloads stay in the tab, so you can safely paste production data without it reaching a third party.
The field table, the method and a worked example are documented after the tool for anyone who wants to check the working.
What do the Cron Expression Parser fields mean?
The Cron Expression Parser uses 1 input. A filled form means you can test one idea immediately instead of sourcing every input first.
| Field | What to enter | Default |
|---|---|---|
| Cron expression | required | 0 9 * * 1-5 |
How does the Cron Expression Parser 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 calculation.
An empty or malformed field stops the calculation rather than being treated as zero.
Worked example
These are the values the Cron Expression Parser loads by default, and the result it produces from them. Below is the same computation the tool performs on load, step by step.
| Cron expression | 0 9 * * 1-5 |
|---|
| Status | Parsed fields |
|---|---|
| Fields JSON | { "minute": "0", "hour": "9", "dayOfMonth": "*", "month": "*", "dayOfWeek": "1-5" } |
How to use it
- Set Cron expression.
- Results update continuously rather than on submit.
- Check Status and Fields JSON on the right.
- 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 will not warn you that a different tool would suit your question better.
Frequently asked questions
Just Cron expression. Every box already holds a working value, so nothing is mandatory before you see a result.
With the values loaded when the page opens, status comes out as Parsed fields. Adjust any field to see how much the answer depends on it.
No record is kept. We never receive what you type, so there is nothing on our side to retain.
No charge. Everything on the page is available without signing in.
There is no estimation step. The result is computed, not inferred.