ForHosting KIT · Developer Utilities

D&D initiative modifier calculator

In Dungeons and Dragons and many other tabletop RPGs, initiative decides who acts first when combat starts.

● BetaFree · in your browser

Use it from WebAPIEmailTelegramApp soon

Your initiative roll is typically a d20 plus an initiative modifier built from your Dexterity modifier and any flat bonuses granted by feats, class or subclass features, and magic items. Adding those pieces by hand is easy until a character sheet carries Alert, a half-proficiency feature, a lucky charm, and a temporary buff all at once—or until a virtual tabletop needs the same total for every build in a party. This D&D initiative modifier calculator accepts the Dexterity modifier you already use on the sheet and optional integer bonuses for feats, class features, and magic items, then returns the summed initiative modifier with a clear expression string you can show next to the character name. The same pure module powers the free browser widget and the API path, so a character builder, a GM prep sheet, and a blog widget never disagree on plus five Alert on top of a plus three Dexterity score.

How to use it

Enter your values in the form above. The tool checks them before calculating and shows the result on the same page.

Check your inputs

Use the labels and units shown next to each field. If something is missing or outside the allowed range, the page points to the field to fix.

Use it again or automate it

Use the browser tool for individual checks and the API when you need the same capability in an automated workflow.

What you can do with it

Get an answer now

Enter one set of values and see the result without building a spreadsheet or script.

Compare scenarios

Change one value at a time and rerun the calculation to understand what affects the result.

Automate repeated work

Use the API when the same calculation needs to run inside your product or workflow.

FAQ

How do I use this capability?

Complete the fields above and run it on this page. The form highlights anything that needs attention.

For developers — API access

Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.

API endpoint

POSThttps://api.kit.forhosting.com/hobby/dnd-initiative-modifier

Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.

Call it from your stack

curl -X POST https://api.kit.forhosting.com/hobby/dnd-initiative-modifier \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"dexterity_modifier":3}'

const res = await fetch("https://api.kit.forhosting.com/hobby/dnd-initiative-modifier", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.KIT_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "dexterity_modifier": 3
  })
});
const { task_id } = await res.json();

import os, requests

res = requests.post(
    "https://api.kit.forhosting.com/hobby/dnd-initiative-modifier",
    headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
    json={
    "dexterity_modifier": 3
},
)
task_id = res.json()["task_id"]

<?php
$res = file_get_contents("https://api.kit.forhosting.com/hobby/dnd-initiative-modifier", false, stream_context_create([
  "http" => [
    "method"  => "POST",
    "header"  => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
    "content" => '{"dexterity_modifier":3}',
  ],
]));
$task = json_decode($res, true);

body := bytes.NewBufferString(`{"dexterity_modifier":3}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/hobby/dnd-initiative-modifier", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)

Example request

{
  "dexterity_modifier": 3
}

Example response

{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "hobby.dnd_initiative_modifier",
  "status": "queued",
  "_links": {
    "result": "/tasks/tsk_…/result"
  }
}

The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.

Pricing

Per request$0.002

Published price — no tokens, no invented credits. A failed task is never charged.

Errors

HTTP	Code	Meaning
`401`	`unauthorized`	Missing or invalid API key.
`402`	`insufficient_balance`	Your balance doesn't cover the task price.
`404`	`unknown_type`	That task type doesn't exist.
`429`	`rate_limited`	Too many requests. Use the webhook instead of polling.

Read the full KIT documentation →