MrTools

MrTools guides

Practical guides for everyday tasks

Clear workflows, real limitations and direct paths to tools that run locally in your browser.

How to reduce an image’s file size

Choose between resizing and compression by identifying whether pixels or encoding cause the file size.

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How to merge PDF files safely

A reliable merge starts with readable source files, deliberate order and a final page check.

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How to format and validate JSON

Formatting makes JSON readable; validation confirms that the data follows JSON syntax.

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How to count words and characters accurately

Word, character and line counts answer different questions and depend on clearly stated rules.

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How to calculate percentage change

Percentage change compares a new value with an old baseline; the denominator and zero case matter.

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Create useful and reliable QR codes

Choose the correct QR content type, keep the payload concise and test the result on another device.

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How to compare financial scenarios

How to compare financial scenarios: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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How to calculate dates and working time

How to calculate dates and working time: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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How to create useful document templates

How to create useful document templates: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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How to review a Chilean document template

How to review a Chilean document template: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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How to clean and verify structured data

How to clean and verify structured data: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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Web quality and accessibility checklist

Web quality and accessibility checklist: a practical workflow for entering information, reviewing assumptions and saving a useful result without uploading data.

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