Embed Calculators

Add free calculator widgets to your blog or website

Business

Conversion

Everyday

Finance

Gaming

Health & Sports

Math

Science

Technology

Compound Interest Calculator

Calculate how your investments grow over time with compound interest and regular contributions.

Discount Calculator

Calculate the final price after applying a single discount. Quick and simple.

Discount Percentage Calculator

Find out what percentage discount was applied by entering the original and final prices.

Multiple Discount Calculator

Calculate the final price after applying several chained discounts and find the total effective discount.

Savings Goal Calculator

Calculate how much you need to save per day, week, month, or year to reach your financial goal on time.

Hong Kong Salaries Tax & Net Salary Calculator

Compute Hong Kong salaries tax and monthly take-home pay for Year of Assessment 2025/26 and 2026/27 with all 9 allowances, 10 deductions, dual progressive vs standard rate comparison, MPF mandatory contributions, the HK$3,000 one-off tax reduction, and provisional tax.

China Mortgage LPR Calculator

Calculate Chinese mortgage payments with the latest LPR rates — commercial, provident-fund and combined loans, using equal-installment or equal-principal repayment.

Percentage Calculator

Calculate percentages instantly: find X% of a number, what percentage one number is of another, or the percentage change between two values.

BMI Calculator

Calculate your Body Mass Index (BMI) instantly. Get your WHO classification, healthy weight range, and personalized recommendations.

Running Pace Calculator

Calculate your running pace, time, or distance. Get splits, speed, and race predictions with the Riegel formula.

Token Calculator

Calculate the cost of using AI language models. Estimate tokens from text and compare pricing across models like GPT-4, Claude, and Gemini.

Mortgage Calculator

Calculate your monthly mortgage payment, total interest, and view a full amortization schedule. Includes property tax, insurance, PMI, and extra payment analysis.

Maharashtra Stamp Duty Calculator

Calculate stamp duty, metro cess, local body tax and registration fee for property purchases in Maharashtra. Covers Mumbai, Pune, Nashik, Nagpur, and rural areas with women concession and gift deed rates.

Loan Calculator

Calculate your monthly loan payment, total interest, and total cost. Compare up to 3 loan scenarios side by side. Supports fixed (annuity) and decreasing payment methods.

Loan Comparison

Compare up to 3 loan scenarios side by side. See which loan costs less in total interest and find the best deal.

Crowdfunding ROI Calculator

Calculate the return on investment for crowdfunding projects. Estimate net profit, annualized ROI, and fees.

Age Calculator

Calculate your exact age in years, months, and days. Find out how many total days, weeks, hours, and minutes you have lived — plus how many days until your next birthday.

Korean Age Calculator (Man nai, Se-neun nai, Yeon nai)

Calculate your Korean age in all three systems — Man nai (legal, since 2023), Se-neun nai (traditional) and Yeon nai (year age) — from a single date of birth.

Date Duration Calculator

Calculate the exact duration between two dates and times. Get results in years, months, days, hours, minutes, and seconds.

Shoe Size Converter

Convert shoe sizes between US, UK, EU, JP, KR, BR, MX, AU and foot length. Instant results for men, women, and kids.

Shoe Size Converter: US to EU

Convert shoe sizes between US and EU instantly. Quick reference charts for men's, women's, and kids' sizes with foot length in cm and inches.

Shoe Size Converter: US to UK

Convert shoe sizes between US and UK instantly. Quick reference charts for men's, women's, and kids' sizes with foot length in cm and inches.

Shoe Size Converter: EU to UK

Convert European to UK shoe sizes instantly. Complete EU to UK size charts for men's, women's, and kids' footwear with foot length measurements.

VAT / Sales Tax Calculator

Calculate VAT, GST, or sales tax instantly. Add or remove tax from any price with automatic rate detection for 30+ countries.

Tapera Calculator (Indonesia)

Calculate your Indonesian Tapera contribution (2.5% employee + 0.5% employer, or 3% self-employed) and project the long-term balance with BP Tapera yield assumptions.

BMR Calculator (Basal Metabolic Rate)

Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Get personalized calorie targets for weight loss, maintenance, and weight gain.

Calorie Calculator (TDEE & Macros)

Calculate your daily calorie needs and macronutrient targets. Get personalized protein, carbs, and fat goals for weight loss, maintenance, or muscle gain based on your TDEE.

Body Fat Calculator

Estimate your body fat percentage from neck, waist (and hip for women) using the US Navy circumference method. Get fat mass, lean body mass, and ACE/ACSM healthy ranges.

Cooking Converter

Convert between any cooking measurements: cups, tablespoons, teaspoons, ml, liters, grams, kg, ounces, and pounds. Ingredient-aware for volume-to-weight conversions.

Length Converter

Convert between metric, imperial, and astronomical length units (millimetre, metre, kilometre, inch, foot, yard, mile, nautical mile, ångström, light-year, AU, parsec) with NIST-grade exact factors.

Area Converter

Convert between metric and imperial area units (square millimetre, square centimetre, square metre, hectare, square kilometre, square inch, square foot, square yard, acre, square mile) with NIST-grade exact factors.

Volume Converter

Convert between metric, US customary, and UK imperial volume units (millilitre, cubic centimetre, litre, cubic metre, cubic inch, cubic foot, cubic yard, US fluid ounce, US pint, US gallon, UK pint, UK gallon) with NIST-grade exact factors.

Force Converter

Convert between SI, gravitational, and CGS force units (newton, kilonewton, dyne, kilogram-force, tonne-force, pound-force, ounce-force, short-ton-force) with NIST-grade exact factors anchored to CGPM 1901 standard gravity.

Torque Converter

Convert between SI and imperial torque units (newton-metre, kilonewton-metre, kilogram-force metre, kilogram-force centimetre, pound-foot, pound-inch, ounce-inch) with NIST-grade exact factors anchored to CGPM 1901 standard gravity and the 1959 international yard and pound.

Pressure Converter

Convert between SI, atmospheric, and gravitational pressure units (pascal, kilopascal, megapascal, bar, millibar, atmosphere, torr, mmHg, psi, kgf/cm², inH2O, cmH2O) with NIST-grade exact factors and conventional liquid-column values.

Angle Converter

Convert between SI and historical plane-angle units (radian, milliradian, degree, gradian, turn, arcminute, arcsecond) anchored to the BIPM SI Brochure definition of the radian.

Energy Converter

Convert between SI, electrical, and thermal energy units (joule, kilojoule, megajoule, watt-hour, kilowatt-hour, thermochemical calorie, IT calorie, kilocalorie, BTU, US therm, electronvolt) with NIST-grade exact factors anchored to the 2019 SI redefinition.

Power Converter

Convert between SI and historical power units (watt, kilowatt, megawatt, mechanical horsepower, metric horsepower / PS, electric horsepower, BTU per hour, kilocalorie per hour, foot-pound per second). Disambiguates the three horsepower variants that vary by hundreds of watts.

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur temperatures. Handles non-multiplicative scales correctly using the SI offset definition (0 °C = 273.15 K exactly, 13th CGPM 1967).

Mass Converter

Convert mass between metric (kg, g, mg, tonne), avoirdupois (lb, oz, stone, short ton, long ton), troy ounce, grain, and the metric carat with NIST-grade exact factors.

Unit Converter

Convert between length, mass, volume, area, temperature, pressure, energy, power, force, torque, and angle units with NIST-grade exact factors.

Cups to Grams Converter

Convert cups to grams and grams to cups for 30 cooking ingredients. Quick fraction buttons, ingredient selector, and reference table.

Tablespoons to ML Converter

Convert tablespoons to milliliters and ml to tbsp. Supports US, metric, and Australian tablespoon standards.

Ounces to Grams Converter

Convert ounces to grams and grams to ounces instantly. Quick reference table for common weight conversions.

Islamic Mahr Calculator

Calculate Islamic mahr (dowry) in your local currency using live gold and silver prices. Supports Mahr Fatimi, minimum mahr, gold-based, silver-based, and income-based methods.

Sleep Calculator

Find the best time to go to bed or wake up based on sleep cycles. Calculate optimal sleep times for 3 to 6 complete 90-minute cycles.

Social Jet Lag Calculator

Measure your social jet lag in hours, find your chronotype, and get a personalized bedtime fix. Based on the Munich ChronoType Questionnaire (MCTQ).

Pregnancy Calculator

Calculate your due date, current gestational age, and pregnancy milestones from your last menstrual period, conception date, IVF transfer, or known due date. Buddhist Era dates supported in Thailand.

Ovulation Calculator

Estimate your next ovulation date, ASRM 6-day fertile window, and the earliest day a home pregnancy test could read positive. Plan three cycles ahead with a stateless calendar visualization.

Buddhist Calendar Converter

Convert dates between the Gregorian calendar (CE) and the Thai Buddhist Era calendar (BE). Handles the pre-1941 Thailand reform automatically.

Hijri Calendar Converter

Convert dates between the Hijri (Islamic) lunar calendar and the Gregorian calendar. Shows AH year, Ramadan and Eid countdowns, and Arabic-Indic numerals.

Hebrew Calendar Converter

Convert dates between the Hebrew (Jewish) and Gregorian calendars. Includes Adar I/II in leap years and upcoming festival countdowns.

Chinese Lunar Calendar Converter

Convert any date between the Gregorian calendar and the Chinese, Vietnamese, or Korean lunar (lunisolar) calendar. See the zodiac animal, sexagenary year, element, solar term and leap-month status instantly.

World Calendars Converter

Convert any date across six world calendar systems at once: Gregorian, Hijri, Hebrew, Persian, Japanese Era, and Buddhist.

Genshin Pity Calculator

Calculate your chance of getting the featured 5★ on the Genshin Impact Character Event, Weapon Event (Epitomized Path), and Standard banners.

HSR Warp Calculator

Calculate your pull probability on Honkai: Star Rail character, Light Cone, and standard warp banners. Mobile-friendly with a plain-language result.

ZZZ Signal Calculator

Calculate your odds on Zenless Zone Zero's Exclusive (Agent), W-Engine, and Stable channels. Target M0–M6 and read the result in plain words.

Wuthering Waves Convene Calculator

Calculate your pull probability for Wuthering Waves featured resonator, weapon, and standard convenes. 100% featured weapon banner supported.

NTE Pity Calculator

Calculate your pull probability on Neverness to Everness (NTE) Limited Character, Arc weapon, and Standard banners. No 50/50 on character banner, Arc 25/75 with failsafe, and Scarborough Fair soft pity.

Arknights: Endfield Pity Calculator

Calculate your pull probability on Arknights: Endfield Chartered Headhunting (limited character), Arsenal Issue (weapon), and Basic Headhunting banners. Dual-counter pity: 80 hard pity that carries between banners, and a 120-pull featured guarantee that resets each banner. No 50/50 failsafe.

Factorio Production Calculator

Know exactly how many assemblers, furnaces, and chemical plants you need for any Factorio recipe. Covers the base game and Space Age, with modules, beacons, and belt throughput — every ratio worked out for you.

Factorio Power Plant Calculator

Size your Factorio power plant in MW. Boilers + steam engines for early game, solar panels + accumulators for renewable Nauvis builds, nuclear reactors with neighbour bonus for megabase density, fusion plants for Aquilo. Covers the base game and Space Age quality tiers.

Satisfactory Production Calculator

Plan any Satisfactory production chain to the recipe. Full graph solver with all 106 alternate recipes, Power Shard overclocking up to 250%, Somersloop production amplification, byproduct routing, and peak-vs-average power for Particle Accelerator, Quantum Encoder, and Converter — every ratio verified against the wiki.

Dwarf Fortress Food and Booze Calculator

Plan your Dwarf Fortress food and booze production. Computes farm tiles, planters, brewers, stills and barrels needed to feed N dwarves year-round, using formulas from dwarffortresswiki.org.

Minecraft Enchanting Probability Calculator

Calculate the exact odds of rolling a specific enchantment from a Minecraft enchanting table. Pick your item, material and bookshelf count (0–15), and see the probability of Fortune III, Efficiency V, Sharpness V and every other enchantment per slot — based on the official Java Edition 1.21 algorithm.

Minecraft XP Calculator

Find the exact experience points to go from any Minecraft level to any other — plus how many mob kills, smelts, or bottles it takes, and roughly how long, based on the official Java Edition 1.21 XP formula.

Stardew Valley Crop Profit Calculator

Find the most profitable Stardew Valley crop. Computes gold per day and total seasonal profit for each crop given your season, days left, farming level, fertilizer, professions and processing route — ranked best to worst.

eDPI Calculator

Calculate eDPI, cm/360 and inches/360 for CS2, Valorant, Apex Legends, Fortnite, Overwatch 2 and other FPS games. See where you land vs pros and convert your sensitivity between games.

CS2 eDPI Calculator

Calculate your eDPI, cm/360 and inches/360 for Counter-Strike 2. Compare your sensitivity against ZywOo, s1mple, NiKo, donk, m0NESY and device.

CS2 Trade-Up Calculator

Compute the exact output skins, probabilities, and predicted floats for any Counter-Strike 2 trade-up contract. Supports knife/glove 5-input contracts, multi-collection mixing, StatTrak, and reverse search.

OpenTTD Cargo Income Calculator

See exactly what each delivery pays in OpenTTD. Pick a cargo, set the distance and days in transit, and the calculator returns £ per trip, £ per tile, £ per day, and the most profitable cargo for that route.

ZDoom Damage and DPS Calculator

Compute exact damage range, expected DPS and time-to-kill for any ZDoom / GZDoom weapon or projectile. Includes the random(1,8) multiplier, STRIFEDAMAGE flag, and a tic-to-seconds converter for ACS scripts.

Clair Obscur: Expedition 33 Attribute & Damage Calculator

Plan attribute points (Might, Agility, Defense, Vitality, Luck) and estimate skill damage for any Clair Obscur: Expedition 33 build. Compare two builds side by side using the game's relative-multiplier damage model.

Simutrans Cargo Revenue Calculator

Calculate per-trip and per-month revenue for any Simutrans-Standard cargo, with the speed bonus floor (bonus_basefactor=125) made explicit. Supports Pak128 and Pak64.

Water Footprint Calculator

Calculate your daily and yearly water footprint in litres or gallons. See the hidden 'virtual water' in your diet, energy, and shopping, and compare against your country's average.

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Free Calculator Widgets for Your Website or Blog

Smart Calculators offers 30+ free, embeddable calculator widgets that you can add to any website, blog, or landing page in under 2 minutes. Each widget is fully responsive, works in 30 languages, and requires no coding knowledge -- just copy the embed code and paste it into your HTML editor.

Whether you run a personal finance blog, a health and fitness site, a real estate portal, or a cooking community, there is a ready-made calculator widget here that adds genuine utility for your readers. Unlike calculator builders that require you to design formulas from scratch, every Smart Calculators widget ships with industry-standard formulas already built in, professionally validated, and localized for your audience's language and currency.

Why Embed a Calculator Widget on Your Website?

Embedding an interactive calculator increases time on page by 40-60% on average, reduces bounce rates, and gives visitors a concrete reason to return. A visitor who calculates their mortgage payment or checks their BMI on your site is far more engaged than one who reads a static paragraph about the same topic.

For bloggers and content creators, calculator widgets turn passive readers into active users. A finance article about compound interest becomes dramatically more valuable when readers can plug in their own numbers and see personalized results right on your page. The same applies to health articles with a BMI calculator, cooking guides with a unit converter, or running blogs with a pace calculator.

From an SEO perspective, embedded calculators increase dwell time and reduce pogo-sticking -- two behavioral signals that search engines use to evaluate content quality. Pages with interactive tools consistently outperform text-only pages for engagement metrics.

How to Embed a Calculator on Your Website

Adding a Smart Calculators widget to your site takes 3 simple steps:

1. Browse the calculator list above and click the "Embed" button on the calculator you want.

2. Choose your preferred theme (light or dark) and preview how the widget will look on your site.

3. Copy the generated embed code and paste it into your website's HTML editor, WordPress block, Wix HTML widget, Squarespace code block, or any platform that accepts custom HTML.

The embed code includes a lightweight script that loads the calculator inside a responsive container. It automatically adapts to the width of its parent element, so it looks great on desktop, tablet, and mobile screens without any extra configuration.

No sign-up is required. No API keys. No monthly limits. The widget works immediately after you paste the code.

Available Calculator Categories

Smart Calculators covers a wide range of topics organized into clear categories, so you can find the right widget for your audience:

Finance: compound interest, mortgage, loan comparison, savings, ROI, crowdfunding ROI, and VAT calculators. Perfect for personal finance blogs, real estate sites, and investment platforms.

Health and Fitness: BMI calculator, BMR (basal metabolic rate) calculator, and running pace calculator. Ideal for health blogs, fitness coaching sites, and wellness communities.

Everyday Tools: discount calculator, multiple discount calculator, percentage calculator, age calculator, and date duration calculator. Great for shopping blogs, coupon sites, and general-purpose content.

Conversion Tools: shoe size converters (US-EU, US-UK, EU-UK), cooking unit converter, cups to grams, tablespoons to mL, and ounces to grams. Essential for international fashion sites, recipe blogs, and cooking communities.

Technology: AI token calculator for estimating API costs across LLM providers. Valuable for tech blogs and developer communities.

New calculators are added regularly. If you embed a widget today, your visitors will automatically get the latest version -- no code updates needed on your end.

What Makes These Widgets Different

Most embeddable calculator services either require you to build formulas from scratch or lock key features behind a paywall. Smart Calculators widgets are different in several important ways.

30 languages built in. Every widget automatically displays in the language matching the embed locale you select. If you run a Spanish-language blog, the calculator interface, labels, and currency formatting will all be in Spanish with euros or the currency of the target market. This is not machine translation -- each locale is independently optimized by native speakers.

Ready-made, validated formulas. You do not need to enter any formulas or configure calculation logic. Every calculator uses industry-standard math that has been verified against official sources. The compound interest calculator uses the standard A = P(1 + r/n)^(nt) formula. The BMI calculator follows WHO guidelines. The mortgage calculator supports both French (annuity) and linear amortization methods.

Completely free with no limits. There is no freemium tier, no monthly view cap, no forced branding, and no account required. You copy the code, paste it, and it works -- permanently.

Light and dark themes. Every widget supports both light and dark themes that you select during configuration. The widget will match your site's look and feel out of the box.

Responsive by default. Widgets adapt to any container width, from a narrow sidebar to a full-width content area. They render correctly on all screen sizes without extra CSS.

Embedding on WordPress, Wix, Squarespace, and Other Platforms

The embed code works on any platform that supports custom HTML. Here is how to add it on the most popular website builders:

WordPress (Block Editor): Add a "Custom HTML" block where you want the calculator to appear, paste the embed code, and publish. The widget renders immediately in both preview and live modes.

WordPress (Classic Editor): Switch to the "Text" tab in the editor, paste the embed code at the desired position, and update the post.

Wix: Add an "Embed a Site" or "Custom Element" component from the Add menu, paste the embed URL, and adjust the frame size.

Squarespace: Add a "Code" block to your page, paste the embed code, and save. The widget will be responsive within the block's width.

Shopify: In the theme editor or blog post editor, switch to HTML view and paste the embed code.

Google Sites: Use the "Embed" option from the Insert menu and paste the URL from the embed code.

For any platform not listed here, the general process is the same: find the HTML or embed section in your editor, paste the code, and save.

Best Practices for Calculator Widget Placement

Where you place a calculator widget on your page matters. Here are tested strategies that maximize engagement:

Place the widget after your introduction but before the detailed article. Readers who arrive from a search query often want to calculate something immediately. Putting the tool near the top lets them get their answer fast, and then they continue reading your content for context and explanation.

Match the widget to the article topic. A blog post about "How to Calculate Compound Interest" should embed the compound interest calculator, not a generic widget. Topic-matched calculators see 3-5x higher interaction rates than mismatched ones.

Use a descriptive heading above the widget. Something like "Try It: Calculate Your Mortgage Payment" gives visitors a clear call to action. This heading also helps search engines understand the interactive content on your page.

Consider sidebar placement for evergreen tools. If your site has a sidebar, a percentage calculator or BMI calculator can serve as a permanent utility that visitors use regardless of which page they landed on.

Do not overload a single page with too many widgets. One or two calculators per page keeps the experience focused. If you want to offer many calculators, link to your own embed page or create a dedicated tools section.

Frequently Asked Questions

Yes, every calculator widget is 100% free with no hidden costs, no monthly view limits, and no account required. You can embed as many calculators as you want on as many pages as you need. There is no premium tier or paywall.

No coding skills are needed. The process is copy-paste: click the Embed button, choose a theme, copy the generated code snippet, and paste it into your website's HTML editor. The entire process takes under 2 minutes.

Yes. In the WordPress Block Editor (Gutenberg), add a Custom HTML block and paste the embed code. In the Classic Editor, switch to the Text tab and paste the code. The widget is fully compatible with all WordPress themes and works on both desktop and mobile.

Yes. Smart Calculators supports 30 languages including Spanish, German, French, Portuguese, Hindi, Arabic, Japanese, Korean, Turkish, and more. When configuring the embed, select the locale that matches your audience, and the entire widget -- labels, currency, number formatting -- will display in that language.

Yes. Every widget is built with responsive design and automatically adapts to the width of its container. It renders correctly on desktop monitors, tablets, and smartphones without any additional CSS or configuration.

No. The embed code loads asynchronously, meaning it does not block your page from rendering. The widget script is lightweight and all calculations run client-side in the visitor's browser, so there is no server processing delay.

You can choose between light and dark themes during the embed configuration. The widget uses a clean, modern design that blends well with most website styles. The responsive container automatically adjusts to match your content area's width.

There is no technical limit, but for the best user experience we recommend 1-2 calculators per page. Each calculator loads independently, so adding multiple widgets will not cause conflicts. For sites that want to offer many calculators, consider creating a dedicated tools or resources page.