住宅・自動車calculator

適正家賃シミュレーター

Avoid becoming "house poor". Determine your comfortable, maximum, and danger rent thresholds by evaluating both your gross income and existing monthly debt commitments.

入力パラメータ

ブラウザ内処理のみ

計算結果と分析

計算準備完了 (¥0)

左側の入力フォームに数値を入力すると、リアルタイムで計算結果と推移グラフが生成されます。

Recommended Rent Limit: $0/month

Recommended Rent Ceiling$0

Rent-to-Income Ratio0.0%

Total Debt-to-Income (DTI)0.0%

Disposable Income Left$0

戦略的インサイト

主な洞察と次のアクション

The standard rule advises spending no more than 30% of gross monthly income on housing.
Existing debt payments reduce your safe borrowing capacity under the 28/36 underwriting guideline.
Enter your income above to see your comfortable and stretch rent ceilings.

セクション1: 計算の仕組み

この計算の仕組み（わかりやすい解説）

The standard 30% rule dictates that rent should not exceed 30% of your gross monthly income. However, if you carry substantial student loans, auto payments, or credit card debt, spending 30% on rent leaves you cash-starved. This tool applies the mortgage underwriting 28/36 rule: total monthly debt plus housing obligations should not exceed 36% of gross income.

セクション2: 数式と計算前提

アルゴリズム数式と計算根拠

計算式:

\text{Max Monthly Rent} = \frac{\text{Gross Annual Income}}{40} = \text{Monthly Gross} \times 0.30

モデルの前提条件:

Assumes stable ongoing monthly earnings.
Assumes tenant pays typical electric/gas utilities on top of base rent (~$150-$200/mo).

セクション3: 実践的なシミュレーション

Comparative Impact Modeling

戦略的な調整によって将来の推移がどう変わるか確認してください:

戦略 A

Baseline Minimum Strategy

Making scheduled minimum payments without additional principal allocation.

Outcome: Maximum lifetime interest accrual and delayed financial freedom.

戦略 B（最適化）

Accelerated Decision Strategy

Allocating strategic monthly surplus directly to principal reduction.

Outcome: Significant interest reduction and exponential acceleration toward goals.

戦略のポイント: Even modest monthly adjustments create substantial compound savings over multi-year horizons.

セクション4: 例外・境界条件

モデルの制限事項と境界条件

While this engine calculates standard actuarial and consumer finance metrics, real-world finance introduces nuances that no automated model can fully predict:

Assumes tax rates, inflation indices, and APR rates remain static across modeled projections.
Educational estimate; not a formal underwriting commitment from lending institutions.
Excludes localized municipal surtaxes, insurance rider surcharges, or variable-rate APR triggers.

よくあるご質問

よくある質問: 適正家賃シミュレーター

What is the "40x Rule" used by NYC and large city landlords?

Many landlords require your annual gross salary to be at least 40 times the monthly rent. For a $2,000/month apartment, you need a minimum salary of $80,000 ($2,000 × 40). This is equivalent to spending 30% of your gross income on rent.

What should I do if rent in my city exceeds 30% of my income?

In ultra-competitive rental markets, take on a roommate to split fixed bedroom costs, look along transit corridors outside city centers, or negotiate for included parking and utilities.