The Key Debt Ratios That Tell the Story
Core debt ratios and their thresholds
| Ratio | How to Calculate | Safe Zone | Danger Zone |
|---|---|---|---|
| Debt-to-Income (DTI) | Total monthly debt payments ÷ gross monthly income | Below 36% | Above 43% |
| Debt-to-Net-Worth | Total liabilities ÷ total net worth | Below 1:1 | Above 2:1 |
| Consumer Debt Ratio | Non-mortgage debt ÷ annual income | Below 15% | Above 30% |
| Housing Cost Ratio | Total housing costs ÷ gross income | Below 28% | Above 35% |
The debt-to-net-worth ratio is particularly revealing. If you owe $400,000 and your assets total $500,000, your debt-to-net-worth ratio is 4:1 — meaning you owe four dollars for every dollar of equity. That’s a thin cushion.
Negative net worth (liabilities > assets) means debt exceeds everything you own. This is common in early career stages. It becomes dangerous in mid-career: a 38-year-old with negative net worth has a structural problem, not a timing problem.
'Good Debt' vs. 'Bad Debt' — The Real Breakdown
Debt classification by type and typical 2025 rates
| Debt Type | Classification | Why | 2025 Rate Range |
|---|---|---|---|
| Mortgage (primary home) | Potentially good | Funds appreciating asset; interest often deductible | 6.2–7.2% |
| Student loan (STEM/medical) | Potentially good | Raises earning capacity significantly | 5–8% |
| Rental property mortgage | Potentially good | Funds income-generating asset | 6.5–8% |
| Auto loan (used car) | Neutral to bad | Funds depreciating asset | 6–10% |
| Student loan (low-ROI degree) | Often bad | Debt may exceed income benefit | 5–8% |
| Credit card balance | Bad | High rate, funds consumption | 20–29% |
| Personal loan for vacations | Bad | Funds consumption with interest cost | 10–20% |
The Critical Threshold: Total Debt Payments vs. Income
The most practical 'too much' test: add up every monthly minimum payment across all debts. Mortgage + car + student loans + credit cards. If this total exceeds 43% of your gross monthly income, lenders consider you over-leveraged — and so should you.
Example: A 36-year-old teacher in Sacramento earning $68,000 gross ($5,667/month) with: mortgage $1,600, car $420, student loans $380, credit card minimum $95. Total: $2,495. Ratio: 44%. She’s at the danger threshold — one unexpected expense away from missed payments.
When Debt Is Destroying Your Net Worth
Debt destroys net worth through two mechanisms: directly (the liability itself reduces your equity) and through interest cost (money paid in interest is money not invested). At 22% credit card interest, every $10,000 balance costs $2,200/year in pure interest — money that has zero asset creation effect.
$25,000 at 22% APR, minimum payments only, takes approximately 47 years to pay off and costs $64,000 in interest alone. Total cost: $89,000. That $25,000 'debt' costs nearly 4× its face value in lifetime wealth destruction.
The Payoff Priority That Protects Net Worth Fastest
- Any debt above 15% APR — attack immediately (debt avalanche or snowball)
- Consumer loans and personal loans above 10%
- Auto loans above 7%
- Student loans above 6%
- Mortgage and low-rate student loans — maintain minimum payments while investing
See How Debt Affects Your Net Worth
Calculate your full financial picture and identify exactly which debts are holding you back.