JPG, PNG or WebP: which image format should you use?
Choose a format based on the image, not just the file extension.
Read the guideTHE TOOLS50 BLOG
A little know-how. A better result.
Practical guides to smaller images, clearer text and calculations you can explain.
15 guides with worked examples, clear steps and tools you can use straight away.
Image tools
How to make an image smaller without guessing
A repeatable way to balance dimensions, quality and file size.
Read the guideHow to reduce an image below 200 KB
A practical resize-and-compress workflow for upload limits, with checks before you submit.
Read the guideHow to resize an image without stretching it
Use width, aspect ratio and cropping correctly when preparing an image for a website or upload form.
Read the guideWhy converting JPG to PNG does not improve image quality
Understand what a format conversion preserves and what it cannot restore.
Read the guideCalculators
Profit margin vs. markup: the difference that changes your price
The same profit produces two different percentages.
Read the guideHow to calculate a percentage change
Measure a change against the value you started with.
Read the guideHow to calculate a discount and the final price
Check savings, sale prices and successive discounts with simple worked examples.
Read the guidePercentage points vs. percent: how to describe a change
Avoid confusing the difference between two rates with their relative increase.
Read the guideText tools
How to remove duplicate lines without losing the order
Clean a pasted list and choose whether capitalization should affect matching.
Read the guideWord count vs. character count: which limit should you check?
Read the right result when preparing an application, description or short piece of text.
Read the guideDeveloper
Base64 is not encryption: what it actually does
Encoding changes a representation, not who can read it.
Read the guideHow to fix common JSON formatting errors
Check quotes, commas and values before pretty-printing a JSON document.
Read the guideHow to convert CSV to JSON without losing leading zeros
Choose a delimiter, use clear headers and preserve text values during conversion.
Read the guideTime & random
How to count days between two dates
Understand elapsed days, inclusive counting and why calendar days are not business days.
Read the guide