URL pattern: /tools/<tool-name>.html
Phase 1: 10 tools. Each page: H1, textarea in/out, actions, ≥200 words copy, 2–3 FAQ, title + meta description + canonical.
Pretty-print JSON
P1Counts words & chars
P1Encode to Base64
P1Decode Base64
P1Percent-encoding
P1Decode URLs
P1Single-line text
P1UPPER / lower / Title
P1Sort lines A→Z
P1URL-safe slugs