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New✅ ValidationCosta Rica ID number validatorEnter 1-0234-0567 and you learn it is a valid personal cédula, stored as 102340567 and shown in its usual hyphenated…NNitroRuns in your browserFreeOpen →New💰 Finance & moneyCosta Rica severance calculatorThirty months on an average ₡600,000, then a dismissal without just cause: the settlement comes to ₡2,040,000 in notice…NNitroRuns in your browserFreeOpen →New💰 Finance & moneyCosta Rica employer payroll charges 2026A ₡1,000,000 monthly salary costs a Costa Rican employer ₡1,268,300 in 2026, because ₡268,300 in social charges, the…NNitroRuns in your browserFreeOpen →New💰 Finance & moneyCosta Rica net salary calculator 2026On ₡1,000,000 gross a month, an employee in Costa Rica takes home ₡883,500 in 2026: ₡108,300 goes to the CCSS and ₡8,200…NNitroRuns in your browserFreeOpen →New💰 Finance & moneyCosta Rica aguinaldo calculatorYour aguinaldo is one twelfth of everything earned from 1 December to 30 November: twelve months at ₡600,000 come to an…NNitroRuns in your browserFreeOpen →New➗ MathNull space calculatorThe rows (1, 2, 3) and (2, 4, 6) have rank 1, so their null space needs two basis vectors: (−2, 1, 0) and (−3, 0, 1).SsamuraiRuns in your browserFreeOpen →New➗ MathLogical NOR calculatorFalse NOR false is true, and every other pair gives false. Enter two true-or-false values and get the NOR result with…PPavilionRuns in your browserFreeOpen →New➗ MathMultiply complex numbersMultiply two complex numbers in rectangular form: (1 + 2i)(3 + 4i) gives −5 + 10i, using (ac − bd) + (ad + bc)i with i²…AabuelaRuns in your browserFreeOpen →New➗ MathMöbius strip calculatorGive the band width and the centreline radius and get the Möbius strip's area and its single edge: a band 1 wide on a…SsamuraiRuns in your browserFreeOpen →New➗ MathLong multiplication calculatorMultiply two whole numbers the schoolbook way and see every partial product: 123 times 45 gives the rows 615 and 4920…AabuelaRuns in your browserFreeOpen →New➗ MathMean calculatorAdd up a list and divide by how many numbers it holds: 2, 4, 6, 8 and 10 sum to 30, so the mean is 6.PPavilionRuns in your browserFreeOpen →New➗ MathLog2 calculatorEnter a positive number and get its base-2 logarithm, the power of two that produces it: log2 of 8 is 3, of one half is…SsamuraiRuns in your browserFreeOpen →

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#1📈 SEOValidate a redirect mapCatch redirect mistakes while the map is still a file: in /a → /b → /c → /d, the route from /a takes three hops and is…GGalaRuns in your browserFreeOpen →#2📄 Documents & PDFConvert HTML to PDFTurn an invoice template or a rendered report written in HTML into a PDF that looks exactly like the page a modern…NNitroAPI$0.040Open →#3📄 Documents & PDFJPG to PDFThree photos of a damaged part, or several receipts snapped on a phone, become one PDF with one page per image, in the…NNitroAPI$0.002Open →#4📄 Documents & PDFURL to PDFKeep a competitor's advertised claims, a government notice or a partner's terms exactly as they appeared on a given…NNitroAPI$0.040Open →#5🌐 TranslationSort a list alphabeticallyWith Spanish rules, “nandu” comes before “ñandú” and “Ñoño”, and “Ángel” sits right after “angel” instead of at the end…GGalaRuns in your browserFreeOpen →#6✅ ValidationValidate a phone numberType +34 600 11 12 22 and you get +34600111222, confirmed as a valid Spanish number of 11 digits, ready for your contact…NNitroRuns in your browserFreeOpen →#7✅ ValidationColor contrast checkerKnow whether text will stay readable for everyone, whatever your own screen shows: dark gray #111827 on white has a…GGalaRuns in your browserFreeOpen →#8🖼️ ImagesAdd a logo to a QR codeAdd your logo to the center of a QR code without breaking it: the error-correction level, the logo's size and the blank…NNitroRuns in your browserFreeOpen →#9🕸️ Web Scraping & MonitoringRemove tracking parameters from a URLTwo UTM tags gone, the id parameter kept and nothing else in the link touched: paste a link to strip known tracking…GGalaRuns in your browserFreeOpen →#10📄 Documents & PDFSplit a PDFCut a three-page PDF every two pages and you get two files: pages 1 and 2, then page 3.NNitroAPI$0.002Open →#11📄 Documents & PDFExtract text from a PDFGet the words a native PDF already contains as plain text in reading order, without fonts, columns or coordinates…NNitroAPI$0.002Open →#12✍️ Text & AISummarize a textNobody on your team has to skim a 4,000-word document again to find the three sentences that matter: paste it in and get…NNitroAPI$0.003Open →

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❤️ Health & fitnessFree
Mueller equation BMR calculator
Get a composition-aware resting calorie floor from four simple measurements: a 30-year-old man of 80 kg and 180 cm splits into 61.42 kg lean and 18.58 kg fat…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Oxford Henry BMR calculator
Estimate your resting calories with the Oxford equations by Henry (2005), built on a broad multi-ethnic dataset: a 30-year-old man weighing 70 kg gets 1583.17…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Schofield BMR calculator
Estimate resting calories with the WHO Schofield equations, which need only weight, sex and age: a 30-year-old man of 70 kg falls in the 30 to 60 band and gets…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Body Roundness Index calculator
Score how round your body shape is from waist and height alone: a waist of 80 cm at 170 cm tall lands in the low band, below a Body Roundness Index of 3.41.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Covert Bailey body fat calculator
Estimate body fat with only a tape measure and your age: a 28-year-old man with a 34-inch waist, 38-inch hips, 11.5-inch forearm and 6.5-inch wrist comes out at…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Deurenberg body fat from BMI
Turn a BMI you already know into a body fat estimate: a 35-year-old man with a BMI of 24.5 comes out at 21.25% body fat under the 1991 Deurenberg equation.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Gallagher body fat calculator
Estimate body fat from BMI, age and sex with the multi-term Gallagher equation: a 30-year-old man with a BMI of 25 comes out at 19.61%.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Jackson-Pollock 3-site body fat for women
Estimate a woman's body fat from three caliper skinfolds and her age: 18 mm at the triceps, 16 mm above the hip bone and 24 mm at the front thigh at age 30 give…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Jackson-Pollock 4-site body fat calculator
Turn four caliper skinfolds into a body fat percentage: a 30-year-old man with 12, 20, 15 and 18 mm at the triceps, abdomen, hip and thigh sums 65 mm and comes…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Parrillo 9-site body fat calculator
Turn nine caliper skinfolds and your weight in pounds into a body fat percentage: sites adding up to 114 mm at 175 lb give 17.59% with the Parrillo formula.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Body surface area calculator
Get body surface area with the Boyd formula from 1935: someone 170 cm tall weighing 70 kg has 1.834670289827 m².
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Body surface area Fujimoto calculator
With the Fujimoto formula, 170 cm and 70 kg give about 1.76 m² of body surface area. Enter height in cm, m or inches and weight in kg or pounds; the tool…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Lean bulk calorie calculator
Enter maintenance calories and a surplus percentage: 2500 kcal with a 10% surplus gives a 2750 kcal daily target, 250 kcal above maintenance.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Calorie target for weight goal
Going from 80 to 75 kg between 1 January and 12 March 2026 on 2500 kcal of maintenance means eating about 1950 kcal a day.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Calorie cycling zigzag planner
Turn a weekly calorie budget into alternating high and low days: 14000 kcal with a 20% zigzag gives 2400 kcal high days and 1466.7 kcal low days, and the week…
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Carb intake calculator
Half of a 2000 kcal day is 1000 kcal from carbohydrate, or 250 grams. Enter your daily calories and the percentage you want from carbs, and the calculator gives…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Conicity index calculator
The conicity index divides your waist in metres by 0.109 times the square root of weight over height, so the higher the score, the more your shape leans toward…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
CSS swim training pace calculator
With a CSS of 1:30 per 100 m, offsets of minus 5, zero and plus 10 seconds give paces of 1:25, 1:30 and 1:40.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Cutting phase calorie calculator
A 20% cut on 2500 kcal of maintenance means a 500 kcal daily deficit and a 2000 kcal cutting target, 3500 kcal over the week.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Dietary energy density calculator
Turns a meal's calories and weight into one comparable figure: 450 kcal on a 350 g plate is about 128.57 kcal per 100 g.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Calories from macronutrients calculator (Atwater)
Turns grams of protein, carbohydrate, fat and alcohol into calories with the Atwater factors: 25 g protein, 40 g carbs and 12 g fat add up to 368 kcal.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
EPOC afterburn estimate calculator
Estimates the extra calories your body burns after a workout ends: 80% intensity for 45 minutes at 70 kg gives about 105 kcal of afterburn.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Fat-free mass calculator
Splits your scale weight into fat and lean mass: at 80 kg with 15% body fat, lean mass is 68 kg and fat mass 12 kg.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Normalized FFMI calculator
Puts athletes of different heights on one lean-mass scale: 68 kg of lean mass at 1.75 m receives a height correction of 0.305 points toward the 1.8 m reference.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Fiber intake per 1000 kcal calculator
Turns total daily calories into a fiber target with one rule, 14 g per 1,000 kcal: 2000 kcal a day means 28 g of fiber.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
FTP from 20-minute test calculator
Estimates functional threshold power from a 20-minute all-out effort: a 280 W average becomes an FTP of 266 W with the classic 95% factor.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Goal calorie adjustment
Turns maintenance calories and a goal into a daily target: 2500 kcal with a 20% fat-loss cut gives 2000 kcal a day, 500 less, or 3500 kcal less a week.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Max heart rate Tanaka calculator
Estimates how high your heart rate can climb at full effort using the Tanaka regression, 208 minus 0.7 times age: 180 bpm at age 40.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Ideal body weight calculator
Estimates adult ideal body weight with the Devine formula from height and sex: a man 170 cm tall gets 65.94 kg, or 145.37 lb.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Ideal body weight Miller calculator
Applies the 1983 Miller formula to height and sex: for a man, 56.2 kg at five feet plus 1.41 kg for every extra inch; for a woman, 53.1 kg plus 1.36 kg per…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Lean body mass Hume calculator
By the Hume equations, a man weighing 80 kg at 180 cm carries about 58 kg of lean mass. Enter weight, height and sex for the estimate taught in exercise…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
MET-minutes per week calculator
Five METs for 30 minutes, five times a week, adds up to 750 MET-minutes, or 12.5 MET-hours. Enter intensity, session length and weekly sessions to get one…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
NEAT calculator
10,000 steps at 70 kg add up to about 311.22 kcal of non-exercise activity in a day. Enter your step count and weight to put a clear walking line in your…
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Normalized power calculator
A perfectly steady ride at 200 W scores a Normalized Power of 200 W and a variability index of 1, while surges and climbs push NP above the average.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Epley one-rep max calculator
Lifting 100 kg for 5 clean reps puts your Epley one-rep max at about 116.67 kg. Enter the weight and reps of a hard set to plan your training percentages…
Aabuela
Runs in your browser
❤️ Health & fitnessFree
One-rep max O'Conner calculator
Lifting 100 kg for 5 reps gives an O'Conner one-rep max of 112.5 kg. Enter the weight and the reps you completed to set training percentages with the linear…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Physical activity level energy calculator
A basal rate of 1700 kcal a day at a moderate activity level, a PAL of 1.75, means a daily need of 2975 kcal.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Barbell plate loading calculator
For 100 kg on a 20 kg bar, load one 25 kg and one 15 kg plate on each side. Enter your target weight, plus your bar and plates if they differ from the standard…
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Protein intake by fitness goal calculator
At 70 kg with a muscle-gain goal, the daily target is 126 g of protein, using 1.8 g per kilo. Pick a goal from sedentary to athlete instead of guessing a g/kg…
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Reciprocal ponderal index calculator
For 1.75 m and 70 kg the reciprocal ponderal index is 0.424625, height divided by the cube root of weight (4.121285).
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Relative strength ratio calculator
Deadlift 100 kg at 80 kg body weight and your relative strength is 1.25 times bodyweight, or 125 %.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
1RM percentage table calculator
With a 100 kg one-rep max, 70 % is 70 kg and 85 % is 85 kg: enter the max you already know and get the whole loading chart from 50 % to 100 % in 5-point steps.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
RER substrate calculator
At an RER of 0.85, half of your energy comes from carbohydrate and half from fat. Enter one measured respiratory exchange ratio between 0.70 and 1.00 and get…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
RMR from fat-free mass calculator
With 60 kg of lean mass and 15 kg of fat mass, the Nelson equation puts your resting metabolic rate at 1608.6 kcal a day.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Schwartz-Malone coefficient calculator
A man totalling 500 kg at 93 kg body weight gets a Schwartz coefficient of 0.574296 and a score of 287.15.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Skeletal muscle mass calculator
A 30-year-old man 175 cm tall with arm, thigh and calf girths of 32, 52 and 36 cm carries about 36 kg of skeletal muscle by the Lee equation.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Skinfold sum body density calculator
A 58 mm skinfold sum, your protocol's published coefficients and an age of 30 give a body density of 1.045465, which the Siri equation turns into a body fat…
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
Daily sodium limit calculator
Get your daily sodium ceiling by age and see it as table salt: at 40 the limit is 2300 mg of sodium, about 5.85 g of salt, and it drops to 1500 mg with high…
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Steps per mile from stride calculator
Divide one mile, 1609.344 metres, by your stride to get your steps per mile: a 0.75 m stride means 2145.792 steps per mile.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Swim pace yards to meters converter
Switch a swim pace between yards and metres at the same speed: 1:15 per 100 yards becomes 1:22 per 100 metres, using the exact 0.9144 metres in a yard.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Cunningham TDEE calculator
With 65 kg of lean mass and a moderate activity level, the Cunningham equation gives a resting burn of 1,930 kcal and a daily total of 2,991.5 kcal.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Thermic effect by macronutrient
A meal with 40 g of protein, 50 g of carbohydrate and 15 g of fat has 495 kcal, and 58.7 kcal of that goes to digestion, leaving 436.3 kcal.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
VO2 reserve calculator
With a VO2max of 50 mL/kg/min and a resting uptake of 3.5, your VO2 reserve is 46.5 mL/kg/min: the aerobic window above rest that training targets are built on.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
VO2 max from 5K race time calculator
A 5K run in 25:00 means an average of 200 metres a minute, which points to an estimated VO2 max of about thirty-eight mL/kg/min.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
Astrand-Ryhming step test VO2 max calculator
A 30-year-old, 70 kg man whose heart rate settles at 150 after the Astrand-Ryhming step test has an estimated VO2 max of 41.467 mL/kg/min.
Aabuela
Runs in your browser
❤️ Health & fitnessFree
VO2 max beep test calculator
Stopping at level 8, shuttle 5 of the 20-metre beep test means 66 shuttles, 1320 metres and an estimated VO2 max of about forty-one and a half mL/kg/min.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
VO2 max Bruce treadmill protocol calculator
A man who lasts 12:30 on the Bruce treadmill protocol stops in stage 5 with an estimated VO2 max of 44.59375 mL/kg/min.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
VO2 max Uth-Sørensen calculator
A maximum heart rate of 190 and a resting pulse of 60 give an estimated VO2 max of about forty-eight and a half mL/kg/min with the Uth-Sørensen method.
Ssamurai
Runs in your browser
❤️ Health & fitnessFree
YMCA 3-minute step test VO2 max calculator
A man whose pulse is 150 in the minute after the YMCA 3-minute step test has an estimated VO2 max of 48.33 mL/kg/min.
PPavilion
Runs in your browser
❤️ Health & fitnessFree
Cycling power-to-weight ratio calculator
Holding 250 watts at 70 kg gives a power-to-weight ratio of 3.57 W/kg, the number cyclists compare for climbing and time trials.
Ssamurai
Runs in your browser

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