Library

Calculator tools

Calculator tools is a Netra Code page for people who need clear rules, not a sales script. Numeric tools: BMI, loan EMI, paint quantities, percentages. Each page shows the method under the result.

calculator tools illustration on Netra Code
Calculator tools — Netra Code

Numeric tools: BMI, loan EMI, paint quantities, percentages. Each page shows the method under the result.

Calculator tools in practice

Read this Calculator tools page together with the tool library and the contact details. Outbound policy pages we keep in view include Google Privacy Policy and W3C WAI when the topic is ads or access.

How this Calculator tools page is edited

We update the Calculator tools when the product changes. We do not invent offices, reviews, or staff. Email corrections rather than posting personal data in a comment.

Does the Calculator tools replace the live tools?

No. Calculators stay on their own URLs. This Calculator tools text is the policy or explainer layer.

Accuracy for the Calculator tools depends on the quality of what you type. Garbage in, garbage out still applies. If you mix units, the Calculator tools cannot guess your intent. Re-read the labels, then run it again.

Mobile use of the Calculator tools should not require pinch-zooming the buttons. If a control overflows, email the URL. Desktop and phone should show the same method for this Tools tool.

Print or PDF export is not required for the Calculator tools. Copy text, or download when the tool offers a file. Do not photograph the screen as your only record if the number matters later.

Language on the Calculator tools page is English. Formulas do not change when you translate the labels in your head. Keep the original units.

Netra Code will not add YouTube or Facebook video downloaders next to the Calculator tools. Social tools here are counters and drafts.

Accessibility: every Calculator tools field should have a visible label. Keyboard users can tab through the form. If a result is only shown as colour, that is a bug — report it.

Performance: the Calculator tools should feel instant for ordinary inputs. Huge files are the exception. Close other tabs if a phone runs out of memory on a merge.

Versioning: if the Calculator tools method changes, the page copy should say so. We would rather document a simplification than hide it.

Teaching: you can use the Calculator tools in a classroom as long as students know it is an estimate. Do not grade someone on a web calculator as if it were a statute.

Slug calculator-tools is the stable URL piece for this Calculator tools. Prefer that permalink in internal links so redirects stay simple.

Competitors exist. The reason to use this Calculator tools on Netra Code is the labelled method, the related tools, and the fact that we do not upsell a download of someone else’s video.

If you need a human, use the contact email. Include the Calculator tools URL and what you typed (never passwords or medical records).

A second pass on the Calculator tools is worth doing after you sleep on the first number. People change an input, forget they changed it, and trust a result that no longer matches the story they tell a doctor, a lender, or a client. Write the inputs down next to the Calculator tools output if anyone else will see it.

Netra Code keeps the Calculator tools on a stable permalink so guides, hubs, and the homepage can point at one URL. If you are documenting a process for a team, link that permalink rather than copying the JavaScript. When the method is updated, everyone who used the link sees the same change.

Finally, the Calculator tools is only useful if you understand the unit on each field. A height in centimetres is not a height in inches. A rate in percent is not a decimal. Re-read the Calculator tools labels every time you come back after a long break.

Accuracy for the Calculator tools depends on the quality of what you type. Garbage in, garbage out still applies. If you mix units, the Calculator tools cannot guess your intent. Re-read the labels, then run it again.

Mobile use of the Calculator tools should not require pinch-zooming the buttons. If a control overflows, email the URL. Desktop and phone should show the same method for this Tools tool.

Print or PDF export is not required for the Calculator tools. Copy text, or download when the tool offers a file. Do not photograph the screen as your only record if the number matters later.

Language on the Calculator tools page is English. Formulas do not change when you translate the labels in your head. Keep the original units.

Netra Code will not add YouTube or Facebook video downloaders next to the Calculator tools. Social tools here are counters and drafts.

Accessibility: every Calculator tools field should have a visible label. Keyboard users can tab through the form. If a result is only shown as colour, that is a bug — report it.

Performance: the Calculator tools should feel instant for ordinary inputs. Huge files are the exception. Close other tabs if a phone runs out of memory on a merge.

Versioning: if the Calculator tools method changes, the page copy should say so. We would rather document a simplification than hide it.

Teaching: you can use the Calculator tools in a classroom as long as students know it is an estimate. Do not grade someone on a web calculator as if it were a statute.

Health

BMI calculator

Body mass index from height and weight.

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Health

BMR calculator

Mifflin–St Jeor basal metabolic rate.

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Health

TDEE calculator

Daily energy use from BMR and activity.

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Health

US Navy body fat

Circumference estimate (not a diagnosis).

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Health

Ideal weight (Devine)

Devine formula estimate.

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Health

Waist-to-hip ratio

Waist divided by hip.

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Health

Max heart rate

220 minus age (estimate).

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Health

Heart rate zones

Five training zones from max HR.

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Health

One-rep max

Epley estimate from a submaximal set.

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Health

Protein intake

Grams per kg of body weight.

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Health

Water intake

Rough daily fluid target.

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Health

Calorie deficit

Weekly loss estimate from a daily deficit.

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Health

Macro split

Protein / carbs / fat from calories.

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Health

Due date

Naegele: LMP plus 280 days.

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Health

Ovulation window

Estimate from cycle length.

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Health

Sleep cycles

Wake times in 90-minute cycles.

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Health

Caffeine remaining

5-hour half-life estimate.

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Health

Steps to calories

Rough burn from steps and weight.

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Health

Running pace

Pace from distance and time.

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Health

Lean body mass

Boer formula estimate.

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Health

Mean arterial pressure

MAP from systolic and diastolic.

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Health

Pulse pressure

Systolic minus diastolic.

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Health

Blood pressure category

AHA adult categories (not a diagnosis).

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Health

Glucose mg/dL ↔ mmol/L

Divide or multiply by 18.

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Health

Ideal weight (Robinson)

Robinson height-weight estimate.

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Health

Katch–McArdle BMR

BMR from lean mass.

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Health

Fasting window

Eating window leftover in 24h.

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Health

UK alcohol units

Units from volume and ABV.

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Health

Smoking cost

Yearly spend from packs and price.

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Health

Waist-to-height ratio

Waist divided by height.

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Health

VO2 max (Uth)

Simple HR-based estimate.

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Health

Pace to speed

km/h from min/km.

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Health

Running calories

MET-style estimate.

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Health

Target HR (Karvonen)

Training HR from rest and max.

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Money

Compound interest

Future value with compounding.

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Money

Simple interest

Principal × rate × time.

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Money

Mortgage payment

Principal and interest only.

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Money

Tip calculator

Tip and per-person split.

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Money

Discount calculator

Sale price after off %.

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Money

Markup calculator

Price from cost and markup.

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Money

Profit margin

Margin from cost and price.

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Money

ROI calculator

Return on investment %.

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Money

Inflation value

Future buying power.

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Money

Hourly to salary

Annual from hourly wage.

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Money

Salary to hourly

Hourly from annual salary.

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Money

Savings goal

Monthly save for a target.

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Money

Emergency fund

Months of expenses.

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Money

Credit card payoff

Months to clear a balance.

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Money

Dividend yield

Dividend / price.

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Money

Break-even units

Fixed cost / contribution.

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Money

Freelance rate

Rate from salary and overhead.

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Money

Overtime pay

Time-and-a-half estimate.

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Money

Raise calculator

New pay after a raise.

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Money

Fuel cost

Trip cost from economy.

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Money

Subscription annual cost

Monthly to yearly.

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Money

50/30/20 budget

Needs / wants / save split.

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Money

Sales tax

US-style tax on a price.

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Money

GST/HST add

Canadian-style tax add.

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Money

Monthly compound growth

Same as compound with m=12.

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Money

APR to monthly rate

Nominal monthly rate.

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Money

Payback period

Investment / annual cash.

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Money

Debt-to-income

Monthly debt / income.

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Money

UK service + tip

Optional service on a bill.

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Money

Currency convert (manual rate)

You supply the rate.

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Money

Monthly contribution FV

Annuity future value.

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Home

Paint calculator

Litres from wall area and coats.

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Home

Tile calculator

Tiles needed with waste.

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Home

Wallpaper rolls

Rolls from perimeter and height.

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Home

Room BTU estimate

Rough heating load.

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Home

Insulation R total

Sum of layers.

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Home

Mortar estimate

Bags from wall m².

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Home

Deck boards

Boards from area and width.

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Home

Gravel tonnes

Tonnes from area and depth.

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Math

X is what % of Y

Share as a percent.

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Math

Average

Mean of comma-separated numbers.

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Math

Ratio simplifier

Divide both by GCD.

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Math

Aspect ratio

Width : height reduced.

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Math

Triangle area

Base × height / 2.

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Math

Pythagoras

Hypotenuse from a and b.

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Math

GPA (4.0)

Average of grade points.

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