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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 →

Popular capabilities

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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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🔬 ScienceFree
Displacement calculator
A body starting at 10 m/s and speeding up at 2 m/s² for 5 seconds ends 75 metres from where it began.
Ssamurai
Runs in your browser
🔬 ScienceFree
Drift velocity calculator
A current of 1.6 A through a 1 mm² wire holding 10²⁸ conduction electrons per cubic metre drifts at only 1 millimetre per second.
Aabuela
Runs in your browser
🔬 ScienceFree
Earth curvature calculator
Over 20,000 m the surface falls a few tens of metres, but from an eye height of 1.7 m part of that bulge is still in view.
PPavilion
Runs in your browser
🔬 ScienceFree
Heat exchanger effectiveness-NTU calculator
A counterflow exchanger with an NTU of 1 and a capacity ratio of 0.5 delivers a little over half of the maximum possible heat transfer.
Ssamurai
Runs in your browser
🔬 ScienceFree
Elastic constants calculator
For steel, a Young's modulus of 200 GPa and a Poisson's ratio of 0.3 are enough to fix the shear and bulk moduli too.
Aabuela
Runs in your browser
🔬 ScienceFree
Electric motor torque calculator
A 1.5 kW motor turning at 1,500 rpm delivers about 9.549 newton-metres at the shaft. Enter the power in watts and the speed in revolutions per minute to get the…
PPavilion
Runs in your browser
🔬 ScienceFree
Electrical mobility
A carrier drifting at 5 centimetres per second in a field of 100 volts per metre has a mobility of 0.0005 square metres per volt-second.
Ssamurai
Runs in your browser
🔬 ScienceFree
E=mc² calculator
One kilogram at rest holds nearly 9 × 10¹⁶ joules, its mass times the speed of light squared. Enter a rest mass in kilograms to get its rest energy in joules…
Aabuela
Runs in your browser
🔬 ScienceFree
Energy to wavelength calculator
A photon carrying 10⁻¹⁹ joules has a vacuum wavelength of about 2 micrometres. Enter a photon energy in joules to get its wavelength in metres, worked out from…
Ssamurai
Runs in your browser
🔬 ScienceFree
Escape velocity calculator
Leaving the Earth, with 5.972 × 10²⁴ kg and a radius of 6,371,000 m, takes a little over 11 kilometres per second.
PPavilion
Runs in your browser
🔬 ScienceFree
Excess electrons calculator
A charge of −3.2 × 10⁻¹⁸ coulombs is 20 extra electrons when you use the classroom value of 1.6 × 10⁻¹⁹ coulombs.
Aabuela
Runs in your browser
🔬 ScienceFree
Exoplanet calculator
Around a star of one solar mass, a planet at 1 AU completes its orbit in 365.25 days. Enter the star's mass plus either the orbital period in days or the…
Ssamurai
Runs in your browser
🔬 ScienceFree
Fan airflow calculator
A 0.4 m fan at 1500 rpm pushes air forward at 10 metres per second in the ideal model, a little over 1 cubic metre per second.
PPavilion
Runs in your browser
🔬 ScienceFree
Fermi level calculator
Copper, with about 8.47 × 10²⁸ conduction electrons per cubic metre, has a Fermi energy near 7 electronvolts.
Aabuela
Runs in your browser
🔬 ScienceFree
Flow rate calculator
A section of 0.01 square metres with fluid moving at 1.5 metres per second carries 0.015 cubic metres per second.
Ssamurai
Runs in your browser
🔬 ScienceFree
Foot-pounds of energy calculator
Muzzle energy in foot-pounds is the weight in grains times the speed in feet per second squared, divided by 450240, the formula printed beside factory load…
PPavilion
Runs in your browser
🔬 ScienceFree
Free fall distance calculator
An object dropped from rest falls 19.6 metres in 2 seconds when gravity is 9.8 m/s², with air resistance ignored.
Aabuela
Runs in your browser
🔬 ScienceFree
Free fall height calculator
If a stopwatch shows a 2-second drop under 9.8 m/s² of gravity, the object was released 19.6 metres up.
Ssamurai
Runs in your browser
🔬 ScienceFree
Frequency of light calculator
A 1-metre wavelength in vacuum gives 299,792,458 Hz, and a 500 nm green line comes out near 6 × 10^14 Hz, the scale of visible light.
PPavilion
Runs in your browser
🔬 ScienceFree
Friction coefficient calculator
Divide the friction force by the normal force and get the coefficient μ: 20 N of friction against 50 N of normal force gives 0.4.
Aabuela
Runs in your browser
🔬 ScienceFree
Friction factor calculator
With a Reynolds number of 100,000 and a relative roughness of 0.0002, the Darcy friction factor is 0.019003236842, in turbulent flow.
Ssamurai
Runs in your browser
🔬 ScienceFree
Froude number calculator
Water moving at 2 m/s with a depth of 1 m under Earth's 9.81 m/s² gives a Froude number of 0.6385508568, a subcritical flow.
PPavilion
Runs in your browser
🔬 ScienceFree
Gear ratio RPM calculator
A 1000 rpm motor turning a 20-tooth gear that drives a 40-tooth gear gives a ratio of 2 and 500 rpm at the output.
Ssamurai
Runs in your browser
🔬 ScienceFree
Gay-Lussac's law calculator
Heat a sealed sample at 1 atm from 300 K to 600 K and its pressure doubles to 2 atm. Give the starting pressure in any unit and both temperatures in kelvin; the…
Aabuela
Runs in your browser
🔬 ScienceFree
Generator power calculator
A 230 V single-phase generator delivering 10 A at a power factor of 0.8 gives 1840 W, or 1.84 kW, of real power.
PPavilion
Runs in your browser
🔬 ScienceFree
Ground speed calculator
At 250 knots true airspeed with a 40-knot tailwind, ground speed is 290 knots; turn that wind into a headwind and it drops to 210.
Ssamurai
Runs in your browser
🔬 ScienceFree
Hair diffraction calculator
A 500 nm laser, a screen 2 m away and dark fringes 10 mm apart give a hair diameter of 0.0001 m, or 100 micrometres.
Aabuela
Runs in your browser
🔬 ScienceFree
Hall coefficient calculator
12 mV of Hall voltage across a strip half a millimetre thick, at 2 mA in a quarter-tesla field, gives a Hall coefficient of 0.012 m³/C.
PPavilion
Runs in your browser
🔬 ScienceFree
Heisenberg uncertainty calculator
Confine a particle to 10^-10 m, an atomic scale, and its momentum spread can be no smaller than about 5 × 10^-25 kg·m/s.
Ssamurai
Runs in your browser
🔬 ScienceFree
Helical coil inductance calculator
Ten turns on a 0.0254 m radius spread over 0.0508 m, a 1-inch by 2-inch air coil, give 3.44827586207 µH.
Aabuela
Runs in your browser
🔬 ScienceFree
Helmholtz resonator calculator
A 1.87-litre cavity with a neck 3.14 cm² in area and 5 cm long resonates at about 100 Hz in air at 343 m/s.
PPavilion
Runs in your browser
🔬 ScienceFree
Hoop stress calculator
A pipe at 1 MPa with a 0.2 m bore and a 5 mm wall carries a hoop stress of 20,000,000 Pa, the circumferential pull that tries to split it along a seam.
Ssamurai
Runs in your browser
🔬 ScienceFree
Hubble's law calculator
A galaxy 100 megaparsecs away recedes at 7000 km/s when the Hubble constant is 70 km/s per megaparsec.
Aabuela
Runs in your browser
🔬 ScienceFree
Hydraulic gradient calculator
Heads of 20 m and 16 m at two wells 100 m apart give a hydraulic gradient of 0.04, with groundwater moving from the first well toward the second.
PPavilion
Runs in your browser
🔬 ScienceFree
Hydraulic radius calculator
A section with 2 m² of flow area and 4 m of wetted perimeter has a hydraulic radius of 0.5 m. Divide area by wetted length to get the characteristic length that…
Ssamurai
Runs in your browser
🔬 ScienceFree
Ideal gas temperature calculator
One mole of gas at 101325 Pa filling 0.022414 m³ sits at about 273 K. Enter pressure in pascals, volume in cubic metres and the amount in moles; the gas…
PPavilion
Runs in your browser
🔬 ScienceFree
Ideal gas pressure calculator
One mole of gas at 298.15 K in 0.024465 m³ exerts about 101325 Pa, roughly one standard atmosphere.
Aabuela
Runs in your browser
🔬 ScienceFree
Ideal transformer calculator
A 240 V primary with 1000 turns and a turns ratio of 0.1 gives 24 V on a 100-turn secondary, a step-down transformer.
Ssamurai
Runs in your browser
🔬 ScienceFree
Immersed weight calculator
A 50 N object displacing 0.002 m³ of water at 1000 kg/m³ reads 30.38 N on a scale, because the water pushes up with 19.62 N.
PPavilion
Runs in your browser
🔬 ScienceFree
Insertion loss calculator
Feed 1 W into a cable or filter, measure 0.5 W at the far end, and the insertion loss is 3.01029995664 dB.
Aabuela
Runs in your browser
🔬 ScienceFree
Internal resistance calculator
A 12 V battery that reads 11 V while delivering 2 A has an internal resistance of 0.5 Ω, with 1 V lost inside the cell.
Ssamurai
Runs in your browser
🔬 ScienceFree
Intrinsic carrier concentration calculator
Textbook silicon values at 300 K, with densities of states of 2.8 × 10^25 and 1.04 × 10^25 per cubic metre and a 1.12 eV bandgap, give an intrinsic carrier…
PPavilion
Runs in your browser
🔬 ScienceFree
Knudsen number calculator
Sea-level air, whose molecules travel about 65 nm between collisions, flowing in a 1 mm channel gives a Knudsen number of 0.000065: plainly continuum flow.
Ssamurai
Runs in your browser
🔬 ScienceFree
J-pole antenna calculator
At 146 MHz on the 2-metre band, a J-pole needs a 1.0266865 m half-wave radiator, a 0.51334325 m matching stub and a 1.54002975 m long element.
Aabuela
Runs in your browser
🔬 ScienceFree
Kepler third law
A satellite 42,164,000 m from the centre of Earth, whose mass is 5.9722 × 10^24 kg, takes 86163.3432753 seconds per orbit: one sidereal day.
PPavilion
Runs in your browser
🔬 ScienceFree
Laser spot size calculator
A 632.8 nm helium-neon beam 5 mm wide, focused by a lens with a 0.1 m focal length, comes to a spot 0.0000161141196782 m across.
Ssamurai
Runs in your browser
🔬 ScienceFree
LED current calculator
A 5 V USB rail, a red LED with a 2 V drop and a 150 Ω resistor give 0.02 A through the diode, with 3 V across the resistor.
Aabuela
Runs in your browser
🔬 ScienceFree
Lensmaker's equation
Get the focal length of a thin lens from its material, the medium around it and its two curved faces: a lens of index 1.5 in air with radii of 0.1 and -0.1 m…
PPavilion
Runs in your browser
🔬 ScienceFree
Linear actuator force calculator
A motor torque of 1 N·m on a screw with a 5 mm lead at 0.9 efficiency pushes with more than 1000 N.
Aabuela
Runs in your browser
🔬 ScienceFree
Lorentz force calculator
A 2 C charge moving at 3 m/s along x, with a 4 V/m electric field along y and a 5 T magnetic field along z, feels 22 N along minus y.
Ssamurai
Runs in your browser
🔬 ScienceFree
Lumen calculator
A 100 candela source shining into 2 steradians sends out 200 lumens. Enter the luminous intensity and the solid angle of the beam and get the luminous flux…
PPavilion
Runs in your browser
🔬 ScienceFree
Magnetic declination calculator
If a landmark lies at 50° true and your compass reads 45°, the local declination is 5° east. Enter both bearings of the same point and get the signed offset…
Aabuela
Runs in your browser
🔬 ScienceFree
Magnetic dipole moment calculator
A loop carrying 2 A around an area of 0.5 m² has a magnetic dipole moment of 1 A·m². Enter the current and the enclosed area of a single flat loop to get its…
Ssamurai
Runs in your browser
🔬 ScienceFree
Magnetic force on a current-carrying wire
A wire carrying 2 A along 0.5 m of a 0.4 T field, at 90° to it, feels a force of 0.4 N. Enter current, length, field and the angle in degrees to get the force…
PPavilion
Runs in your browser
🔬 ScienceFree
Magnetic moment calculator
A 10-turn coil carrying 2 A around 0.05 m² has a magnetic moment of 1 A·m². Enter current, number of turns and loop area to get the moment of a whole coil, not…
Aabuela
Runs in your browser
🔬 ScienceFree
Magnitude of acceleration
Components of 3 and 4 m/s² along x and y give an acceleration of 5 m/s². Enter the axis components, leave the third empty for motion in a plane, and get the…
Ssamurai
Runs in your browser
🔬 ScienceFree
Manometer calculator
A 0.2 m difference in a water column, at 1000 kg/m³ and 9.81 m/s², means 1962 Pa. Enter the column height difference, the liquid density and gravity to turn a…
PPavilion
Runs in your browser
🔬 ScienceFree
Mass to density calculator
An object of 12 kg that fills 3 m³ has a density of 4 kg/m³. Enter the mass you weighed and the volume you measured to get the density, with a clear refusal…
Ssamurai
Runs in your browser
🔬 ScienceFree
Maximum height projectile motion
A ball launched at 20 m/s and 45° under a gravity of 9.8 m/s² rises just over 10 m above its launch point.
Aabuela
Runs in your browser
🔬 ScienceFree
Mixed-air temperature calculator
Mixing 2 kg/s of air at 10 °C with 2 kg/s at 30 °C gives a blend at 20 °C. Enter the temperature and mass flow of each stream to get the adiabatic mixed-air…
PPavilion
Runs in your browser

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Get your key

Create an account with your email and add balance when you need it. No subscription, no sales call.

2

Call the endpoint

One authenticated POST. The API returns a task_id immediately — copy-paste snippets in five languages on every page.

3

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Receive a signed webhook the moment it's ready, or fetch a signed link. A failed task is never charged.

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