ForHosting KIT · Developer Utilities

Protein intake by fitness goal calculator

A protein intake by fitness goal calculator answers a search people actually type: how many grams of protein should I eat for muscle gain, fat loss, endurance, or everyday maintenance?

● BetaFree · in your browser

Run — free How it works & API

Use it from WebAPIEmailTelegramApp soon

Sports nutrition education usually expresses protein as grams per kilogram of body weight, then multiplies by mass—but many athletes and coaches do not want to pick a raw g per kg number first. They want a goal label that maps to a transparent educational target, then a clear daily gram total. This tool takes body weight in kilograms and a fitness goal such as sedentary, maintenance, endurance, strength, muscle gain, fat loss, or athlete, looks up the matching grams-per-kilogram factor from a fixed table, multiplies, and returns the daily protein goal in grams plus the resolved goal and factor. The arithmetic is deterministic pure math with no network calls, no random seeds, and no medical diagnosis. Missing weight, non-numeric values, non-positive mass, and unknown goals fail with invalid input so bad form data never masquerades as a meal plan. The free browser widget and the paid API share one isomorphic function, so coaching sheets and automation pipelines never disagree on the same weight and goal.

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 is daily protein by fitness goal calculated?

The tool looks up an educational grams-per-kilogram factor for your fitness goal, then multiplies: daily_protein_g = weight_kg × grams_per_kg(goal). For example, 70 kg at muscle_gain (1.8 g/kg) yields 126 g.

Which fitness goals are supported?

sedentary (0.8), maintenance (1.2), endurance (1.4), strength (1.6), muscle_gain (1.8), fat_loss (2.0), and athlete (2.2) grams per kilogram per day. Common synonyms such as bulk or cutting are accepted and normalized.

Is this medical advice?

No. Table values are transparent educational defaults from commonly cited ranges, not individualized clinical prescriptions. Consult a qualified professional for personal nutrition care.

What happens if weight is zero or the goal is unknown?

The request fails with invalid_input. Non-positive weight and goals that do not resolve to the table are rejected rather than inventing defaults.

What does it cost?

The browser tool is free and runs locally. API requests use prepaid KIT balance at $0.002 per successful item; invalid input is not charged.

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/health/protein-by-goal

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/health/protein-by-goal \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"weight":70,"goal":"muscle_gain"}'

const res = await fetch("https://api.kit.forhosting.com/health/protein-by-goal", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.KIT_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "weight": 70,
    "goal": "muscle_gain"
  })
});
const { task_id } = await res.json();

import os, requests

res = requests.post(
    "https://api.kit.forhosting.com/health/protein-by-goal",
    headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
    json={
    "weight": 70,
    "goal": "muscle_gain"
},
)
task_id = res.json()["task_id"]

<?php
$res = file_get_contents("https://api.kit.forhosting.com/health/protein-by-goal", false, stream_context_create([
  "http" => [
    "method"  => "POST",
    "header"  => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
    "content" => '{"weight":70,"goal":"muscle_gain"}',
  ],
]));
$task = json_decode($res, true);

body := bytes.NewBufferString(`{"weight":70,"goal":"muscle_gain"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/health/protein-by-goal", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)

Example request

{
  "weight": 70,
  "goal": "muscle_gain"
}

Example response

{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "health.protein_by_goal",
  "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 →