Guides

Practical guides

Short, accurate explanations of the ideas behind everyday tools. Each guide links to the tool you can use to try it yourself.

Revenue 8 min read

How Google AdSense and Google Play Payouts Work: Estimated vs Finalised Earnings, FX and Bookkeeping

Estimated vs finalised AdSense earnings, the monthly payment timeline and threshold, why payments get held, and how to record foreign-currency income.

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Encoding 9 min read

Base64 Encoding Explained: How It Works, Where It Is Used and Common Myths

Learn how Base64 turns 3 bytes into 4 characters, what the trailing = means, how Base64URL differs, and why Base64 is not encryption.

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Date & time 7 min read

Unix Timestamps Explained: Seconds vs Milliseconds, Time Zones and the Year 2038 Problem

What a Unix timestamp is, how to tell 10-digit from 13-digit values, converting between UTC and local time, daylight saving pitfalls and the 2038 problem.

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Encoding 7 min read

URL Encoding (Percent-Encoding) Guide: Why Text Turns Into %20 and %EC%95%88

Which characters are allowed in a URL, how percent-encoding works, why spaces become %20 or +, and how to avoid double encoding.

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Security 7 min read

Hash Functions Made Simple: MD5 vs SHA-1 vs SHA-256 and How to Use Them

The three properties of a good hash, why MD5 and SHA-1 are retired for security, and how to use hashes for file integrity and password storage.

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Security 7 min read

How to Create a Strong Password: Length, Entropy and Password Managers

How to calculate password entropy, why length beats complexity rules, which patterns to avoid and how to use a password manager.

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Data 6 min read

UUID Guide: v4 vs v7 and Using UUIDs as Database Primary Keys

UUID structure, how versions differ, why collisions are practically impossible, and why UUID v7 is overtaking v4 for database primary keys.

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Data 7 min read

Fixing JSON Syntax Errors: The 7 Most Common Mistakes and How to Clean Up JSON

JSON basics, seven mistakes that cause parse errors, pitfalls with big numbers and dates, and how to turn JSON into classes or database tables.

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Data 7 min read

CSV vs JSON: When to Use Each and What to Watch When Converting

Structural differences between CSV and JSON, why Excel garbles UTF-8 CSV files, quoting rules for commas and quotes, and how to flatten nested data.

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Date & time 6 min read

How to Read and Write Cron Expressions: The Five Fields and Common Examples

What each of the five cron fields means, how to use *, /, - and commas, common schedules, and the pitfalls around day fields and time zones.

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QR & barcodes 7 min read

Making QR Codes That Scan: Error Correction Levels, Print Size and Barcodes

How QR codes work, choosing error correction (L, M, Q, H), minimum print size and quiet zone, why codes fail to scan, and QR vs product barcodes.

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Calculation 6 min read

Percentage Calculations Explained: Percent Change, Percentage Points, Stacked Discounts and VAT

The four basic percentage formulas, percent versus percentage points, why 20% off plus 10% off is not 30%, and how to back out tax from a gross price.

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Date & time 7 min read

Date Calculations Without the Off-by-One: D-Days, Anniversaries, Age and Months Old

How counting the first day changes D-day and anniversary results, how to calculate age in years, and how calendar-month ages and month-end dates work.

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How we write guides

Every article is written and reviewed by the AIBIZAP team while building and testing the related tool. We cite official specifications where they matter and update articles when tools or standards change. Found a mistake? Please tell us through the contact page.