About Calc Tani

Why We Exist

The same input can produce different results when the effective year, taxable scope, rounding rules, or personal eligibility changes. Calc Tani therefore publishes the reference date, formula, assumptions, and material exclusions behind each number. Results are estimates; important filing, contract, or medical decisions still require confirmation from an official source or qualified professional.

Operating Principles

• Up-to-date rates — Salary estimates use the earned-income withholding table effective March 2026 plus the applicable 2026 insurance rates and limits. Other tools publish their own reference dates in the interface and methodology. When a primary source changes, code, explanations, and regression tests are reviewed together; individual eligibility and employer treatment still require separate confirmation.
• Local-only computation — Salary, health, and transaction amounts are computed in the browser. Exchange lookup sends currency codes, period, and date—but not the conversion amount—to the site API. Feedback plus optional analytics and advertising processing are disclosed separately in the Privacy Policy.
• Verifiable formulas — Each calculator's formula and source is documented on the Methodology page.
• Core features stay free — Display advertising covers our costs, but no calculator feature is ever gated or hidden behind ads.

How We Verify Content

The current release is reviewed against the checks below, and affected checks are repeated when content changes:

1. Official cross-check against NTS, National Pension Service, and Health Insurance Corporation data.
2. Automated regression checks against official examples, calculation invariants, and known boundary cases.
3. Boundary testing (zero, max, upper/lower thresholds).
4. Bilingual content review (Korean and English).

Who Makes This

Calculators and articles are maintained and published under the responsibility of Jeokjeongin (적정인), the site operator. The operator is a software developer who started Calc Tani after personally checking calculation rules during salary negotiations, a job change, and a jeonse contract. Key rates and formulas are compared with primary sources from the responsible agencies; the Methodology page records those sources and material exclusions. The operator also runs the developer-tool site teck-tani.com, which is why the contact address uses that domain (admin@teck-tani.com).

Recent Updates

2026-09-20 — Added visible titles, source-check dates, scope, and exclusions to all 16 calculators; re-audited guide-index ad gating, editorial standards, accessibility, and social metadata.

Entries before March 2026 date from the period when these calculators ran on teck-tani.com.

• 2026-09-05 — Reworked AdSense consent, privacy disclosures, and 404 ad blocking; re-audited calculation accuracy, primary sources, accessibility, mobile interaction, and performance site-wide.
• 2026-08-30 — Rebuilt the homepage, header, and footer around a published 2026 reference table. Applied the Aug 27 Bank of Korea rate rise (3.00%) the same week, moving the jeonse conversion cap to 5.00%.
• 2026-08-20 — Applied H2 2026 figures across the site: 0.20% securities transaction tax, 4.75% rent conversion cap (base rate 2.75%), and the new pension income bands (0.41M–6.59M KRW). Removed duplicate content blocks.
• 2026-07-29 — Removed 92 templated currency-pair pages, expanded the methodology page, and added the 2027 minimum wage guide (11 guides total).
• 2026-07-04 — Major content expansion across all tools, revised privacy policy, and 2 new guides.
• 2026-04-15 — Launched the guide hub (8 articles published).
• 2026-03-24 — Sitemap and SEO metadata overhaul; added missing canonical coverage.
• 2026-03-12 — Split the 16 calculators out of teck-tani.com onto the standalone calc-tani.com domain.
• 2026-02-19 — Updated for 2026 insurance rates and retirement tax deductions (while on teck-tani.com).
• 2025-12 — Added the 16th calculator (Stock Return) (while on teck-tani.com).

Contact

We welcome bug reports, calculation disputes, and requests for new calculators. Contact page leads directly to the operator.