What does English-as-default
cost you?

Methodology — what the math actually does

The calculator estimates two separate things and adds them.

1) Cognitive overhead. Bilingualism research consistently finds that operating in a second language imposes a 10–25% executive-function load, depending on proficiency and task complexity. We use 15% — the middle of the range. Your hourly equivalent is derived from your annual income (income ÷ 2,000 working hours). Then:

• cognitive hours / year = weekly L2 hours × 52 × 0.15
• cognitive tax = cognitive hours × hourly rate

2) Career-premium gap. Multiple studies on salary outcomes for L2 English speakers in English-dominant organizations report a 5–15% compensation gap, varying by domain. We use conservative domain-specific rates: science / academia (10%, where English-language publication is career-critical), tech and finance (8%), generic knowledge work (6%), creative / media (4%), hospitality / service (2%). English natives pay 0%.

Lifetime uses a flat 35-year working horizon, uncompounded. Income is assumed constant — a deliberately conservative choice, since real incomes usually rise. If we compounded 3% annual growth, the lifetime number would roughly double.

This is a directional estimate, not a precise forecast. Individual circumstances vary enormously. Your actual tax could be lower (strong L2 proficiency, mixed-language workplace) or higher (high-stakes negotiations, academic publishing, lead client work). Numbers round to three significant figures to avoid false precision.

References: research on bilingualism and executive-function load, salary studies of L2 English speakers in global knowledge work, and the broader language-economics framework discussed in The $38 Trillion Language Tax. We explicitly don’t make country-specific tax claims, because they require local cost-of-living and wage-distribution data that would widen the confidence interval beyond usefulness.