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Showing 121–140 of 580 tools
Electric Power Calculator
Electrical power in watts = voltage × current.
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Electrical Conductivity Converter
Convert electrical conductivity between listed units.
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Electrical Energy Calculator
Calculate energy delivered by constant power as power × duration.
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Electrical Resistance Converter
Convert a quantity using the listed fixed unit factors.
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Electrical Resistivity Converter
Convert electrical resistivity between listed units.
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Electrostatic Force Calculator
Signed Coulomb force = ke × q1 × q2 / distance².
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Ellipse Area Calculator
Ellipse area = π × semi-axis a × semi-axis b.
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Ellipse Perimeter Calculator
Estimate ellipse perimeter with Ramanujan’s second approximation.
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Ellipsoid Volume Calculator
Find ellipsoid volume as 4πabc/3.
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Email Header Analyzer
Read unfolded email headers and recorded delivery hops. Inspect authentication claims as pasted text; this page does not independently verify SPF, DKIM or DMARC.
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Email Validator
Check a bounded email address syntax.
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Encode File To Base64 Converter
Encode arbitrary file bytes as standard Base64, without guessing a text encoding.
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Energy Converter
Convert a quantity using the listed fixed unit factors.
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Entropy Converter
Convert entropy between the listed units.
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Env To JSON Converter
Read simple KEY=value or export KEY=value lines; strip matching outer quotes and keep each value as a string.
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EPS to SVG Converter
SVG paths from supported vector EPS commands. Interpret explicit PostScript path, color, transform and graphics-state operators into SVG.
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EPUB to HTML Converter
One self-contained HTML file in EPUB spine order. Read an unencrypted EPUB package, sanitize chapter markup and join its reading-order content.
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EPUB to MOBI converter
A legacy MOBI6 text ebook. Extract supported EPUB chapter text and write a Palm database with a MOBI6 header and UTF-8 HTML records.
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EPUB to PDF converter
An image-only PDF of extracted EPUB chapter text. Extract EPUB text in spine order, wrap it on canvas pages and embed those page images in a PDF.
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EPUB to TXT Converter
Extract chapter text from an unencrypted EPUB in its recorded reading order. Download the text without images, page layout or navigation files.
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