家計・支出planner

Irregular Income Budget Planner

Designed for freelancers, sales professionals, and gig workers. Structure your baseline survival budget around lean months and establish a buffer fund.

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。

Baseline Survival Budget: $0/month

Survival Floor (Needs)$0

Lowest Month Cushion$0

Hill-and-Valley Buffer Target$03-Month Cash Holding Account

Average Month Overflow$0

戦略的インサイト

主な洞察と次のアクション

Variable income requires budgeting off your leanest months, not your average earnings.
Calculate the exact buffer fund needed to survive slow seasons without debt.
Build a predictable personal payroll system from fluctuating earnings.

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）

Variable income requires the "Hill-and-Valley" strategy. Instead of budgeting around your average month, set your permanent monthly living standard strictly to your LOWEST historical month. In high-earning months, surplus cash fills a dedicated holding account (the buffer). In lean months, you draw from the buffer to pay yourself a predictable "salary".

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:

R = f(X_1, X_2, \dots, X_n) \quad \text{subject to standard actuarial bounds}

モデルの前提条件:

Income is after business deductions and estimated quarterly tax payments.
Assumes holding buffer is maintained in an accessible savings account.

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: Irregular Income Budget Planner

How much should I set aside for taxes on variable income?

As a general rule, set aside 25% to 30% of every incoming check into a separate business tax account immediately before paying yourself personal income.

What do I do during a sequence of three bad months?

Your 3-to-6 month hill-and-valley buffer fund exists specifically to absorb consecutive slow quarters without forcing you to borrow on credit cards.