Mieterhöhungs-Tragbarkeitsprüfung

The Rent Increase Affordability Check applies the standard '30% rule' for housing affordability — that rent should not exceed 30% of gross monthly income — to a proposed new rent. The 30% benchmark dates to the 1969 Brooke Amendment to federal housing law and remains HUD's official affordability standard. Households spending over 30% on housing are 'cost-burdened'; over 50% are 'severely cost-burdened' — categories used in federal housing policy and academic research. US housing reality: 47.5% of renter households are cost-burdened (over 30%) per 2022 Census American Community Survey — up from 38% in 2000. Severely cost-burdened renters grew to 23.4% (over 50% of income on rent). The 30% rule is increasingly aspirational rather than achievable in high-cost markets where median rent in cities like SF, NYC, LA, Boston, San Diego requires 50%+ of median household income. In contrast, mid-cost markets (Indianapolis, Pittsburgh, Cleveland, St. Louis) keep median rents under 25% of median income. The calculator inputs current monthly income (gross, before taxes), current rent, and proposed new rent. Computes current rent-to-income ratio, new ratio, percentage increase, and viability flag (under 30% = affordable, 30–50% = stretched, over 50% = severely burdened). Useful for evaluating lease renewal negotiations, deciding whether to accept proposed increase or hunt for new apartment, and planning relocation decisions. Negotiation context: rent increases over 5% annually are above typical CPI shelter inflation; over 10% is aggressive in most markets. Tenants facing >5% increases have leverage in soft rental markets — landlords prefer renewing existing tenant ($0 turnover cost) to finding new tenant ($1,000–3,000 turnover cost in vacancy, repairs, screening). Comparative market data from apartment search sites strengthens negotiation position. In markets with rent control (NYC, LA, SF, Berkeley, DC), increases are statutorily capped (1.5–10% depending on jurisdiction).

PrimeCalcPro provides professional-grade tools trusted by businesses and academics.

1. 1Step 1 — Enter monthly household income (gross, before taxes — HUD standard uses gross)
2. 2Step 2 — Enter current monthly rent (include all fixed charges: parking, pet fee, mandatory amenity fees)
3. 3Step 3 — Enter proposed new rent from landlord notice or apartment listing
4. 4Step 4 — Calculator computes current rent-to-income ratio
5. 5Step 5 — Computes new ratio at proposed rent
6. 6Step 6 — Calculates percentage increase
7. 7Step 7 — Flags affordable (<30%), stretched (30–50%), or severely burdened (>50%)

• !Using net income instead of gross — 30% rule is based on gross income per HUD
• !Forgetting to include parking, pet fee, amenity fee in monthly housing cost
• !Comparing to outdated 30% threshold without considering local market reality
• !Accepting increase without checking comparable rents — landlord may be testing limits
• !Forgetting moving costs ($1,500–3,000) when comparing 'move or stay' decision