Deficit Timeline
Map Your Progress.
Fat loss is math, not magic. Use this calculator to predict exactly how many weeks it will take to reach your goal weight based on your daily caloric deficit. Remember: slow, sustainable progress beats crash dieting every single time.
Weight Loss Timeline Calculator
Disclaimer: This tool is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
You will reach your goal on:
Based on losing 1.0 per week.
let currentUnit = 'lbs';
function setUnit(unit) { currentUnit = unit; const btns = document.querySelectorAll('.toggle-btn'); btns.forEach(btn => btn.classList.remove('active'));
if (unit === 'lbs') { btns[0].classList.add('active'); document.getElementById('curWeightLabel').innerText = 'Current Weight (lbs)'; document.getElementById('tarWeightLabel').innerText = 'Target Weight (lbs)'; } else { btns[1].classList.add('active'); document.getElementById('curWeightLabel').innerText = 'Current Weight (kg)'; document.getElementById('tarWeightLabel').innerText = 'Target Weight (kg)'; } }
function calculateTimeline() { let currentWeight = parseFloat(document.getElementById('currentWeight').value); let targetWeight = parseFloat(document.getElementById('targetWeight').value); const deficit = parseFloat(document.getElementById('deficit').value);
if (!currentWeight || !targetWeight || currentWeight <= targetWeight) { alert('Please enter valid weights. Current weight must be greater than target weight for a deficit.'); return; } let weightToLose = currentWeight - targetWeight; // 1 lb of fat is approx 3500 calories. 1 kg of fat is approx 7700 calories. let caloriesPerUnit = currentUnit === 'lbs' ? 3500 : 7700; let totalCaloriesToLose = weightToLose * caloriesPerUnit; let daysRequired = Math.ceil(totalCaloriesToLose / deficit); let targetDate = new Date(); targetDate.setDate(targetDate.getDate() + daysRequired); const options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' }; document.getElementById('dateResult').innerText = targetDate.toLocaleDateString(undefined, options); let lossPerWeek = (deficit * 7) / caloriesPerUnit; document.getElementById('rateResult').innerText = lossPerWeek.toFixed(1) + ' ' + currentUnit; document.getElementById('results').style.display = 'block'; }
let currentUnit = 'lbs';
function setUnit(unit) { currentUnit = unit; const btns = document.querySelectorAll('.toggle-btn'); btns.forEach(btn => btn.classList.remove('active'));
if (unit === 'lbs') { btns[0].classList.add('active'); document.getElementById('curWeightLabel').innerText = 'Current Weight (lbs)'; document.getElementById('tarWeightLabel').innerText = 'Target Weight (lbs)'; } else { btns[1].classList.add('active'); document.getElementById('curWeightLabel').innerText = 'Current Weight (kg)'; document.getElementById('tarWeightLabel').innerText = 'Target Weight (kg)'; } }
function calculateTimeline() { let currentWeight = parseFloat(document.getElementById('currentWeight').value); let targetWeight = parseFloat(document.getElementById('targetWeight').value); const deficit = parseFloat(document.getElementById('deficit').value);
if (!currentWeight || !targetWeight || currentWeight <= targetWeight) {
alert('Please enter valid weights. Current weight must be greater than target weight for a deficit.');
return;
}
let weightToLose = currentWeight - targetWeight;
// 1 lb of fat is approx 3500 calories. 1 kg of fat is approx 7700 calories.
let caloriesPerUnit = currentUnit === 'lbs' ? 3500 : 7700;
let totalCaloriesToLose = weightToLose * caloriesPerUnit;
let daysRequired = Math.ceil(totalCaloriesToLose / deficit);
let targetDate = new Date();
targetDate.setDate(targetDate.getDate() + daysRequired);
const options = { weekday: 'long', year: 'numeric', month: 'long', day: 'numeric' };
document.getElementById('dateResult').innerText = targetDate.toLocaleDateString(undefined, options);
let lossPerWeek = (deficit * 7) / caloriesPerUnit;
document.getElementById('rateResult').innerText = lossPerWeek.toFixed(1) + ' ' + currentUnit;
document.getElementById('results').style.display = 'block';
}