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Practical guides

• How to Resize an Image Without Stretching It

  Resize a photo to the dimensions you need, preserve its aspect ratio and choose an output format. See a worked pixel example and avoid common mistakes.

• JPG vs PNG: Which Format Should You Use?

  Choose JPG or PNG for photos, screenshots and transparent graphics. Learn what conversion changes and why converting to PNG does not restore lost detail.

• How to Compress an Image for an Upload Limit

  Reduce an image file for an upload limit using dimensions, output format and quality. Compare results without promising lossless JPG compression.

• How Much Concrete Do You Need for a Slab?

  Calculate a rectangular slab’s concrete volume in cubic feet, cubic yards or cubic meters, with a worked example and clear bag-yield assumptions.

• How to Calculate Square Footage of a Room

  Calculate floor area from room dimensions, split irregular rooms into rectangles and keep material allowances separate from measured square footage.

• How to Format and Validate JSON

  Format JSON for reading, fix common syntax errors and understand what validation can check. Includes a valid example and cautions about numeric precision.