I Built DeutschRechner.de — 500+ German Calculators With a Friend

Description and use

DeutschRechner.de delivers 511 accurate German calculators and 100+ guides, addressing breadth and depth gaps. It uses static generation, a YAML content schema, and rigorous audits to maintain correctness at scale.

Problem

Existing German calculator sites had breadth and depth gaps, missing many categories and providing shallow, inaccurate tools.

Outcome

Achieved a scalable, accurate calculator platform with 511 tools, overcoming breadth and depth gaps, and establishing a repeatable audit and content workflow.

Workflow

• 1. Identify breadth and depth gaps by auditing existing sites.
• 2. Define a content schema with required fields (formula, examples, commonMistakes, faq).
• 3. Store calculator data in YAML, separate from code.
• 4. Generate static pages upfront (static‑first).
• 5. Use vanilla TypeScript for interactive calculators.
• 6. Audit constants for internal consistency and update from primary sources.
• 7. Build a sitemap pass to set accurate lastmod dates.
• 8. Perform functional audits and coverage scripts to catch bugs.
• 9. Publish and iterate with periodic re‑audits.

Evidence

511 calculators across 22 categories, plus over 100 long‑form guide articles

Source

Static‑first — pages are generated up front, not rendered per‑request

Source

Audit that flagged internal inconsistencies first (the same named constant with two different values across sibling calculators)

Source