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Estimate federal tax
Capital Gains Tax Calculator
Estimate the federal tax from selling stocks, ETFs, mutual funds, or crypto -- and see how timing, losses, or spreading gains across years could change the result.
Method and sources included
Free planning tools · no account required
Financial calculators for real-life decisions.
Run the numbers for debt, retirement, savings, taxes, income, and investing—then see the method, assumptions, and sources behind the estimate.
- Calculations run in your browser
- Formula and limitations shown
- Stable URLs for sharing
- working calculators
- 12
- required to start
- No sign-in
- interactive calculations
- In-browser
- methods and sources
- Transparent
The calculator library
Find the right tool for the next decision.
Search by topic or narrow the library by goal. Each result opens a working calculator with its formula version, assumptions, limitations, related guides, and references.
Showing 12 calculators
Free · interactive · documented
Popular
Grow savings
Compound Interest Calculator
Calculate how your money grows over time with compound interest -- model recurring contributions, compounding frequency, fees, and inflation to see your real future balance.
Method and sources included
Popular
Planning tool
FIRE Calculator
Calculate your FIRE number, savings rate, and path to financial independence. See how many years until you can retire early, based on the 4% rule and your own numbers.
Method and sources included
Popular
Model a home sale
Home Sale Tax Calculator
Estimate the federal tax on selling your home -- including the Section 121 exclusion of up to $250,000 ($500,000 married) of gain from tax.
Method and sources included
Popular
Model rental property
Rental Property Sale Tax Calculator
Estimate the federal tax on selling a rental property, including unrecaptured Section 1250 depreciation-recapture gain taxed at up to 25%.
Method and sources included
Popular
Compare banking costs
Checking Account Cost Calculator
Compare the modeled annual net cost of two checking accounts using service fees, waiver eligibility, ATM use, overdrafts, returned payments, other fees, average balance, and APY.
Method and sources included
Popular
Plan retirement
Retirement Savings Calculator
Project retirement savings with monthly contributions and a constant-return scenario, then compare the result with a 4% first-year withdrawal planning target.
Method and sources included
Popular
Pay down debt
Debt Payoff Calculator
Compare debt avalanche and debt snowball payoff timelines with monthly interest, minimum payments, extra payments and payment rollover.
Method and sources included
Build a safety buffer
Emergency Fund Calculator
Estimate an emergency-savings range from essential monthly expenses, income structure, job stability, current savings and monthly contributions.
Method and sources included
Manage cash flow
50/30/20 Budget Calculator
Compare take-home income and actual spending with the flexible 50% needs, 30% wants and 20% savings or debt-payment rule of thumb.
Method and sources included
Track your position
Net Worth Calculator
Build a point-in-time personal balance sheet by totaling assets and liabilities, with category summaries and an asset-to-debt ratio.
Method and sources included
Popular
Estimate income
2026 Federal Paycheck Calculator
Estimate 2026 federal income tax, employee Social Security and Medicare tax, pretax deductions and net pay before state and local taxes.
Method and sources included
Built for clearer choices
Useful estimates without pretending the future is certain.
A calculator should help you compare choices, not hide complexity behind one impressive-looking number. FinanceFirst keeps the inputs editable and the model visible.
Scenario view
Change an input. Compare the outcome.
Your starting pointEditable
Scenario AEditable
Scenario BEditable
Step 1
Enter a scenario—not personal identifiers
Use balances, rates, time periods, or contributions. Account numbers and identifying details are never needed.
Step 2
Compare the result, not just the headline number
Adjust an input and watch how payoff time, savings, tax, cash flow, or projected growth changes.
Step 3
Check the method before acting
Read the documented assumptions, limitations, source links, and related guidance attached to every published tool.
Trust comes from showing the work.
Financial tools are only as useful as their scope. We separate educational estimates from personalized advice and keep source and update information near the result.
Read our editorial standardsMethods you can inspect
Formula explanations, assumptions, limitations, and references live on the tool page.
No account barrier
Open a calculator and start a scenario without creating a profile or entering contact details.
Context after the result
Move from the estimate into related guides, glossary definitions, and original research.
Clear YMYL boundaries
Tax, investment, credit, and legal limitations are stated instead of hidden in promotional copy.
Go beyond the estimate
Continue with context.
Use the result as a starting point, then check the evidence, definitions, and rules that shape the decision.
Evidence
Original research reports
Explore source-linked datasets and FinanceFirst analysis of household financial trends.
ExploreDefinitions
Plain-English glossary
Understand tax, debt, banking, investing, and retirement terms used in the tools.
ExploreAccountability
Corrections and updates
See how to report a possible error and how FinanceFirst handles corrections.
ExploreWhat you can model
One library, several financial decisions.
FinanceFirst calculators connect general financial education with an editable scenario. They do not replace a lender quote, tax return, payroll system, investment plan, or professional review.
Debt, budgeting, and emergency savings
Compare debt payoff order, review a 50/30/20 reference budget, estimate a cash reserve, or model the annual cost of a checking account.
Personal finance guidesRetirement, investing, and net worth
Project contributions and compound growth, estimate a retirement target, compare a FIRE scenario, or build a point-in-time personal balance sheet.
Retirement guidesPaychecks, capital gains, and property taxes
Estimate 2026 federal paycheck amounts or model federal tax scenarios for investments, a home sale, and rental property activity.
Tax guidesCommon questions
Before you run the numbers.
What the tools cost, how they handle inputs, and what an estimate can—and cannot—tell you.
Which financial calculator should I start with?
Start with the decision you need to make next. Use the debt payoff calculator to compare repayment methods, the paycheck calculator to estimate federal take-home pay, the emergency fund calculator to set a cash target, or the retirement calculator to test a long-term savings scenario.
Are FinanceFirst calculators free?
Yes. Every published calculator is free to use and does not require an account or sign-in.
How accurate are the calculator results?
Results are planning estimates based on the inputs and assumptions shown on each page. They can help you compare scenarios, but they cannot reproduce every lender, payroll, tax, market, or household rule.
Where do the formulas and rates come from?
Each calculator explains its method and links to primary sources when an external rate, limit, tax rule, or planning convention applies. Formula versions and important limitations are shown on the calculator page.
Does FinanceFirst store my calculator inputs?
The interactive calculations run in your browser and no account is required. Do not enter account numbers, Social Security numbers, addresses, or other identifying information into a planning tool.
Can I cite or link to a FinanceFirst calculator?
Yes. Each published calculator has a stable canonical URL plus a documented method, assumptions, and references. When citing a result, also record the inputs and access date because laws, limits, and formulas can change.
FinanceFirst calculators provide educational planning estimates, not personalized financial, investment, tax, accounting, insurance, or legal advice. Verify important information with primary sources and an appropriately qualified professional before acting.