Setting Cron Triggers

Set a Cron Trigger for your Worker.

Last updated Sep 4, 2026

export default {
    async scheduled(controller, env, ctx) {
        console.log("cron processed");
    },
};

interface Env {}
export default {
    async scheduled(
        controller: ScheduledController,
        env: Env,
        ctx: ExecutionContext,
    ) {
        console.log("cron processed");
    },
};

from workers import WorkerEntrypoint, Response

class Default(WorkerEntrypoint):
    async def scheduled(self, controller, env, ctx):
            print("cron processed")

import { Hono } from "hono";

interface Env {}

// Create Hono app
const app = new Hono<{ Bindings: Env }>();

// Regular routes for normal HTTP requests
app.get("/", (c) => c.text("Hello World!"));

// Export both the app and a scheduled function
export default {
    // The Hono app handles regular HTTP requests
    fetch: app.fetch,

    // The scheduled function handles Cron triggers
    async scheduled(
        controller: ScheduledController,
        env: Env,
        ctx: ExecutionContext,
    ) {
        console.log("cron processed");

        // You could also perform actions like:
        // - Fetching data from external APIs
        // - Updating KV or Durable Object storage
        // - Running maintenance tasks
        // - Sending notifications
    },
};

Set Cron Triggers in Wrangler

Refer to Cron Triggers for more information on how to add a Cron Trigger.

If you are deploying with Wrangler, set the cron syntax (once per hour as shown below) by adding this to your Wrangler file:

{
    "$schema": "./node_modules/wrangler/config-schema.json",
    "name": "worker",
    // ...
    "triggers": {
        "crons": [
            "0 * * * *"
        ]
    }
}

"$schema" = "./node_modules/wrangler/config-schema.json"
name = "worker"

[triggers]
crons = [ "0 * * * *" ]

You also can set a different Cron Trigger for each environment in your Wrangler configuration file. You need to put the [triggers] table under your chosen environment. For example:

{
    "env": {
        "dev": {
            "triggers": {
                "crons": [
                    "0 * * * *"
                ]
            }
        }
    }
}

[env.dev.triggers]
crons = [ "0 * * * *" ]

Test Cron Triggers using Wrangler

The recommended way of testing Cron Triggers is using Wrangler.

Cron Triggers can be tested using Wrangler by passing in the --test-scheduled flag to wrangler dev. This will expose a /cdn-cgi/local/scheduled route which can be used to test using a HTTP request. To simulate different cron patterns, a cron query parameter can be passed in.

npx wrangler dev --test-scheduled

curl "http://localhost:8787/cdn-cgi/local/scheduled?cron=*+*+*+*+*" # Python Workers

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