Embeddable Calculators for Modern Teams

52 rigorously tested financial, medical, health, climate, and business calculators. No iframe — styles can't leak in or out. Integrate world-class tools into your product in seconds.

Live Integration Sandbox

+56 more →
// Match your brand with data attributes
<div data-exactcalcs-widget="bmi"
     data-theme="light"
     data-api-key="your_key"></div>
// Load the secure script
<script src="https://exactcalcs.com/exactcalcs-widget.js" async></script>
BMI Calculator

Calculate body mass index with local overrides.

Calculated Body Mass Index:23.6 Normal
Normal
A BMI between 18.5 and 25 is considered normal and healthy.
How this is calculated

Body Mass Index is weight (kg) divided by height (m) squared, with the standard WHO adult categories. We also show BMI Prime (BMI ÷ 25) — values over 1.0 are above the healthy range.

The Universal Registry

A comprehensive suite of 52 specialized calculators, ready to deploy in seconds.

BMI Calculator

Standard & metric body mass index calculations.

Mortgage Amortization

Visual loan payoff schedules & interest breakdowns.

EV Charging Cost

Charging cost and range added per session.

Budget & Cash Flow Planner

Monthly income split across spending categories.

Mortgage Pro Estimator

Extra payments, PMI, and full amortization detail.

Target Heart Rate Zones

Target training zones from your resting rate.

Emergency Fund Planner

Months of expenses to keep in reserve.

Body Fat %

US Navy physical body fat estimation method.

Net Worth & Liquidity Planner

Assets minus liabilities, itemized.

Blood Alcohol Content

Widmark formula BAC estimation over time.

BMR & TDEE

Basal Metabolic Rate profiling for energy needs.

Body Type

Somatotype morphology analysis and categorization.

Only on ExactCalcs

Breast Cancer Risk (Gail Model)

NCI-validated Gail Model risk estimator.

Calorie Calculator

Total daily energy expenditure based on activity.

Calories Burned

MET-based specific activity tracking.

CHADS2 Score

Clinical stroke risk assessment methodology.

Colorectal Cancer Risk

Freedman model clinical risk assessment.

Pregnancy Due Date

Gestational timeline and milestone estimation.

HAS-BLED Score

Major bleeding risk scoring system.

Investment Growth

Compound interest and portfolio growth forecasting.

Only on ExactCalcs

ISTH Bleeding Assessment Tool

Standardized bleeding assessment tool.

Lean Body Mass

Fat-free muscle mass estimation formulas.

Macronutrient Calculator

Targeted Protein/Carb/Fat ratio goal setting.

Melanoma Risk

Clinical skin cancer risk point scoring.

Mortgage Calculator

Comprehensive P&I, property taxes, and insurance.

Ovulation Calculator

Fertility window and conception tracking.

Loan Payment

Standardized monthly payment modeling.

Period Tracker

Cycle length prediction and logging.

Retirement Calculator

Long-term future savings and withdrawal planner.

Debt Payoff: Snowball vs Avalanche

Snowball vs avalanche payoff comparison.

Only on ExactCalcs

Rent vs Buy

Cumulative rent vs buying net cost, with breakeven year.

Inflation-Adjusted Savings

What your savings will really be worth in today's money.

Take-Home Pay (US)

US federal tax + FICA net pay estimate.

Savings Goal Calculator

Required monthly contribution to hit a target.

Home Electricity Cost

Monthly electricity cost across your appliances.

Appliance Running Cost

Day/month/year running cost for one appliance.

Only on ExactCalcs

Solar Payback Calculator

Years until a solar system pays for itself.

Fuel vs EV Cost Comparison

Gas vs electric cost per mile driven.

Waist-to-Height Ratio

Waist-to-height ratio against its health cutoff.

Calorie Deficit Planner

Daily deficit needed to reach a goal weight.

Protein Intake Calculator

Daily protein target from weight and training load.

Water Intake Calculator

Daily hydration target from weight and activity.

Sleep Debt Calculator

Sleep debt accumulated across the week.

Only on ExactCalcs

Meeting Cost Calculator

What a meeting costs in salary, ticking live.

Only on ExactCalcs

SaaS Runway & Burn Rate

Months of cash left at your current burn rate.

Subscription Cost Tracker

What your subscriptions really cost over 5 years.

Only on ExactCalcs

Time Savings / Automation ROI

Dollar value of a small daily time savings.

Only on ExactCalcs

Creator RPM / Revenue Calculator

Content revenue from views and RPM.

Tip Calculator

Tip amount and the per-person split.

Molarity Calculator

Mass, volume, and molarity of a solution.

Dilution Calculator

Stock-to-final-concentration dilution volumes.

Lab Unit Converter

Clinical lab values between SI and US units.

Extra plan

Stop showing blank fields to people you already know.

Point a webhook at your own API and a calculator opens pre-filled with a specific visitor's real numbers — their income, their height, whatever your system already has.

  1. 1Your API returns a plain JSON object for whichever visitor is loading the page.
  2. 2We fetch it server-side on every load — never from the visitor's browser, never exposing your auth token.
  3. 3Matching keys pre-fill the calculator. Anything your endpoint is slow, down, or wrong about just falls back to normal defaults — silently.
Read the full contract

Without a webhook

Weight (kg)

Height (cm)

With your webhook

Weight (kg)

82

Height (cm)

178
your-api.example.com/lead-data
// Your endpoint returns:
{
  "weight": 82,
  "heightCm": 178
}
// Keys matching the calculator's own fields pre-fill it — no separate mapping step.

Simple, usage-based pricing

Every plan gets all 49 calculators, styled to match your site. Start free, upgrade when you outgrow the quota.

Free

For trying it out — no card required.

$0/mo
  • 100 calculator loads / month
  • All 49 calculators, every theme
  • Unlimited domains
Get your API Key

Base

For a site with real traffic.

$30/mo
  • 2,000 calculator loads / month
  • Everything in Free
  • Email support
Get your API Key
Webhooks

Extra

Feed calculator inputs from your own API.

$50/mo
  • 10,000 calculator loads / month
  • Everything in Base
  • Webhooks — connect your own API to a calculator's inputs, so it opens pre-filled with your visitor's real data instead of blank defaults
Get your API Key

Need the technical details? Read the API docs

WordPress plugin

No code — just a block, a widget, or a shortcode.

Every calculator is also a native WordPress block, an Elementor widget, and a shortcode — same API key, same live rendering, no iframe, nothing to build.

Block inserter
exactcalcs

ExactCalcs Calculator

Embed any of 49 calculators