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Showing 421–440 of 580 tools
RMS Calculator
Calculate the root mean square of supplied values.
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Robots.txt Generator
Generate robots.txt from a user-agent token and newline-separated allow and disallow paths.
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ROI Calculator
Calculate simple return on investment from the initial cost, final value, additional income, and costs.
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Roman Numeral Converter
Convert between integers and canonical Roman numerals.
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ROT13 Converter
Apply the reversible ROT13 substitution to ASCII letters.
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Rotate Image
Rotate the bitmap by a right angle and export PNG.
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Rotate PDF
Rotate every page of a local PDF clockwise by 90, 180 or 270 degrees. Save the changed orientation without rasterizing the page text and vectors.
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Rotational Kinetic Energy Calculator
Rotational kinetic energy = Iω²/2.
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Round Image Corners
Clip source pixels to a rounded rectangle and save transparent PNG.
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Rounding Calculator
Round a number to a chosen number of decimal places.
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RTF to DOCX converter
A DOCX containing extracted RTF text. Extract text with the RTF reader and create Word paragraphs in a DOCX package.
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RTF to TXT Converter
Extract plain text from pasted RTF source. Read paragraphs, tabs, escaped ANSI bytes and Unicode text without retaining document formatting or embedded objects.
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Running Pace Calculator
Calculate running pace per kilometre and per mile from a distance and elapsed time.
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Sagitta Calculator
Find the minor-arc sagitta as r(1 − cos(θ/2)).
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Salary to Hourly Calculator
Convert annual gross salary into an hourly rate from your hours per week and paid weeks per year.
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Sales Tax Calculator
Calculate sales tax and the total price from a pre-tax subtotal and a rate you enter.
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Schema Markup Generator
Build an escaped application/ld+json script using the selected Schema.org type.
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Scientific Notation Converter
Convert decimal numbers to normalized scientific notation and back using digit-based arithmetic.
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Screen Resolution Calculator
Total pixels = width × height; PPI = the square root of (width² + height²), divided by diagonal inches.
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Sector Area Calculator
Sector area = angle / 360 × π × radius².
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