401k – Kalkulačka
Použijte 401k – Kalkulačka pro rychlé a přesné výsledky.
Jak používat tuto kalkulačku
- Zadejte Current Age
- Zadejte Retirement Age
- Zadejte Annual Salary (Kč)
- Zadejte Your Contribution (%)
- Zadejte Employer Match (%)
- Klikněte na tlačítko Vypočítat
- Přečtěte si výsledek zobrazený pod kalkulačkou
How the 401(k) Calculator Works
This calculator projects your 401(k) balance at retirement using compound interest on your growing contributions and employer match. Each year, your existing balance grows by the assumed return rate, and new contributions (yours + employer match) are added.
The compound growth formula: FV = PV × (1+r)^n + PMT × [((1+r)^n − 1) / r]
Where: FV = future value (projected balance), PV = current balance, r = annual return rate, n = years until retirement, PMT = annual contribution (employee + employer match).
Concrete example: Age 30, current balance 575,000 Kč salary 1,725,000 Kč contributing 10% (172,500 Kč/year), employer matches 50% up to 6% (1,725,000 Kč × 6% × 50% = 51,750 Kč/year), 7% return, retiring at 65 (35 years):
- Annual contributions: 224,250 Kč (172,500 Kč + 51,750 Kč)
- Projected balance at 65: approximately 37,145,000 Kč
Start 5 years later (age 35, same parameters, 30 years): projected balance drops to approximately 24,725,000 Kč — a 12,420,000 Kč difference from just 5 years of delay. This illustrates why starting early matters enormously.
401(k) Contribution Limits and Rules
The IRS sets annual limits on 401(k) contributions, adjusted periodically for inflation:
| Year | Employee Limit (Under 50) | Catch-Up (Age 50–59, 64+) | Special Catch-Up (Age 60–63) | Total Max (Employee + Employer) |
|---|---|---|---|---|
| 2024 | 529,000 Kč | 172,500 Kč | N/A | 1,587,000 Kč |
| 2025 | 540,500 Kč | 172,500 Kč | 258,750 Kč (new SECURE 2.0) | 1,610,000 Kč |
| 2026 | 540,500 Kč | 172,500 Kč | 258,750 Kč | 1,610,000 Kč |
The SECURE 2.0 Act (2022) introduced a higher catch-up contribution limit for those aged 60–63, effective 2025. This allows accelerated savings in the final working years — particularly valuable for late starters or those who paused contributions during difficult periods.
The employer total limit (1,610,000 Kč in 2026) includes all employer contributions: match, profit sharing, and non-elective contributions. High earners at companies with generous profit-sharing plans can sometimes reach this ceiling.
Maximizing Employer Match: Free Money You Can't Ignore
Employer matching is the highest-return investment available to most employees — it's an immediate 50–100% return before any market gains. Not capturing the full employer match is the most expensive financial mistake in retirement planning.
Common match structures:
| Match Structure | Example (Salary 1,840,000 Kč) | Max Match Value |
|---|---|---|
| 100% match up to 3% salary | Contribute ≥3% (55,200 Kč) → get 55,200 Kč match | 55,200 Kč/year |
| 50% match up to 6% salary | Contribute ≥6% (110,400 Kč) → get 55,200 Kč match | 55,200 Kč/year |
| 100% match up to 6% salary | Contribute ≥6% (110,400 Kč) → get 110,400 Kč match | 110,400 Kč/year |
| 25% match up to 10% salary | Contribute ≥10% (184,000 Kč) → get 46,000 Kč match | 46,000 Kč/year |
Vesting schedule: Many employers require you to work a minimum period before the match is fully "yours." Cliff vesting = full match after X years (e.g., 3-year cliff). Graded vesting = percentage increases each year (e.g., 20% per year over 5 years). Always check your plan's vesting schedule — it significantly affects the real value of changing jobs.
Traditional 401(k) vs Roth 401(k): Which Is Better?
Many employers now offer both traditional and Roth 401(k) options. The key difference is when you pay taxes:
| Feature | Traditional 401(k) | Roth 401(k) |
|---|---|---|
| Tax treatment of contributions | Pre-tax (reduces current taxable income) | After-tax (no current deduction) |
| Investment growth | Tax-deferred | Tax-free |
| Withdrawals in retirement | Taxed as ordinary income | Tax-free (qualified distributions) |
| Required Minimum Distributions | Start at age 73 | None (after SECURE 2.0) |
| Best if... | You're in a high tax bracket now, expect lower rate in retirement | You're in a low/medium bracket now, expect higher rate in retirement |
Practical guidance: Young people in early career years are often in lower tax brackets — Roth often makes sense. Mid-career high earners in peak earning years may benefit more from traditional pre-tax contributions. Many financial planners recommend splitting contributions between both for tax diversification in retirement.
Example: Contributing 172,500 Kč to a Traditional 401(k) saves 37,950 Kč in taxes today (22% bracket). Contributing to Roth pays tax now but all growth and withdrawals are tax-free — if that 172,500 Kč grows to 1,725,000 Kč over 30 years, the entire amount comes out tax-free from a Roth vs all taxed as ordinary income from Traditional.
Investment Allocation and Expected Returns
The rate of return you assume dramatically affects projected balances. A 1% difference in annual return over 35 years changes a 23 KčM projection to roughly 18,400 KčK (at 6% vs 7%). Understanding realistic return expectations is critical for honest planning:
| Asset Class | Historical Annual Return (rough) | Volatility |
|---|---|---|
| S&P 500 (large cap US stocks) | 10% nominal, 7% real | High |
| International stocks | 7–9% nominal | High |
| US bonds (aggregate) | 4–5% nominal | Low |
| Balanced (60% stock / 40% bond) | 7–8% nominal | Moderate |
| Target-date fund (20+ yrs out) | 7–9% nominal | Moderate |
Most 401(k) calculators use 6–7% as the default, which represents a balanced portfolio after inflation. For planning purposes, using a 6% real return (adjusted for inflation) is conservative but appropriate for most scenarios.
Allocation by age rule of thumb: "110 minus your age" in stocks is a common starting point (e.g., at age 30: 80% stocks, 20% bonds). Target-date funds automatically adjust this allocation as you approach retirement — they're a sensible default for most 401(k) investors.
Withdrawal Rules and Retirement Income Planning
Understanding when and how to access your 401(k) money is as important as accumulating it:
- Age 59½: Penalty-free withdrawals begin. Withdrawals taxed as ordinary income (traditional) or tax-free (Roth).
- Age 55 rule: If you separate from your employer in or after the year you turn 55, you can take penalty-free withdrawals from that employer's 401(k) — useful for early retirees.
- Age 73: Required Minimum Distributions (RMDs) must begin for traditional 401(k). RMD amount = account balance ÷ IRS life expectancy factor (roughly 3.6–4% at age 73).
- Early withdrawal (before 59½): 10% penalty plus income tax, unless exceptions apply (disability, first-time home purchase via IRA, substantially equal payments, etc.).
Sustainable withdrawal rate: The classic "4% rule" (from the Trinity Study) suggests withdrawing 4% of your portfolio annually in retirement is sustainable for 30 years across historical market scenarios. On a 34,500,000 Kč balance, that's 1,380,000 Kč/year. Combined with Social Security and any other income, this determines how much you need to accumulate.
Frequently Asked Questions
How much should I contribute to my 401(k)?
At minimum, contribute enough to get the full employer match — that's an immediate 50–100% return. Beyond that, most financial planners recommend saving 10–15% of gross income total for retirement (including employer match). If you started late, aim for 15–20%. Maximize contributions if possible — the annual limit (540,500 Kč in 2026) is an opportunity that doesn't carry over.
What is a good rate of return for a 401(k)?
Historical long-term returns: S&P 500 averages ~10% annually (nominal), ~7% after inflation. A diversified balanced portfolio (60/40 stocks/bonds) has averaged ~7–8% nominal, ~5–6% real. For conservative planning, use 6% real return. For aggressive stock-heavy portfolios with a long time horizon, 7–8% is reasonable. Past returns don't guarantee future results.
When can I withdraw from my 401(k) without penalty?
Penalty-free withdrawals begin at age 59½. The "Rule of 55" allows penalty-free withdrawals at 55 if you've separated from your employer. Required Minimum Distributions must begin at age 73. Early withdrawals before 59½ incur a 10% penalty plus income tax, with limited exceptions.
What happens to my 401(k) if I change jobs?
You have four options: (1) Leave it with your former employer (only if the plan allows and the balance is above 115,000 Kč), (2) Roll it to your new employer's plan (if allowed), (3) Roll it to a Traditional IRA (common, no tax consequences), (4) Cash it out (not recommended — triggers income tax + 10% penalty, and destroys compound growth). Always roll over, never cash out.
Should I choose Traditional or Roth 401(k)?
If you're in a low or medium tax bracket now (under 24%) and expect equal or higher rates in retirement, Roth is generally better. If you're in a high bracket now (32%+) and expect lower income in retirement, Traditional pre-tax often wins. When unsure, splitting contributions between both provides tax diversification — some money taxed now, some later.
What if I can't afford to maximize my 401(k)?
Prioritize in order: (1) Get the full employer match first — this is always the highest priority. (2) Pay off high-interest debt (above 7–8%). (3) Build a 3–6 month emergency fund. (4) Then increase 401(k) contributions as budget allows. Even 1% increases per year (automatically triggered with raises) compound meaningfully over decades.
How much do I need to retire?
A common target is 25× your expected annual expenses (based on the 4% withdrawal rule). If you expect to spend 1,380,000 Kč/year in retirement, you need 34,500,000 Kč. Adjust for Social Security income: if Social Security pays 460,000 Kč/year, you need 1,380,000 Kč − 460,000 Kč = 920,000 Kč from savings annually → 23,000,000 Kč target. Use the calculator to project whether your current savings rate gets you there.
"Contributions to a 401(k) plan reduce your taxable income in the year they are made and grow tax-deferred until withdrawal. Employees who contribute at least enough to capture the full employer match are effectively receiving additional tax-advantaged compensation."
Naposledy aktualizováno: March 2026