Functional DemoSaaS

Tax Burden Simulator

A tax-planning simulator that estimates federal, state, and self-employment burden, surfaces deductions, and builds CPA-ready reports.

What it solves

Most people do not understand their true tax burden until it is too late. Individuals and business owners struggle with unclear estimates, missed deductions, poor quarterly planning, mixed personal and business income, self-employment tax, and standard-vs-itemized choices, and end up guessing how much cash to reserve for taxes instead of planning ahead.

Built for W-2 employees, freelancers, contractors, creators, consultants, and small-business owners (sole proprietors, LLCs, S-corps); secondarily CPAs, tax preparers, bookkeepers, and financial coaches.

Overview

Tax Burden Simulator helps individuals and business owners estimate personal and business tax obligations, discover potential deductions, compare planning scenarios, plan quarterly payments, and generate clean CPA-ready reports — without needing to understand tax forms. A guided intake turns income, expenses, deductions, and credits into estimated taxable income, federal/state/self-employment taxes, quarterly payments, effective and marginal rates, and a safe reserve recommendation. A deduction discovery engine with confidence levels, a scenario comparison mode, and an AI planning assistant round it out, with explicit disclaimers that it is planning, not filing or CPA advice.

What this demonstrates

The core is a transparent, configurable tax-year calculation engine (federal, self-employment, deductions, quarterly estimates, effective/marginal rates) with a deduction-discovery and confidence layer that avoids guaranteeing eligibility, plus scenario comparison and CPA report/PDF generation. It adds workspaces with owner/advisor/viewer roles, an AI assistant grounded with a deterministic mock fallback, and a keys-later architecture where every optional integration is inert until its key is set.

What makes it different

This is not a tax filing app. Tax Burden Simulator helps you estimate what you may owe and what could reduce it before tax season arrives.

Taxes must feel simpleAvoid legal and tax jargon.
Always show assumptionsEvery calculation is clearly labeled an estimate.
Never legal or CPA advicePlan, don't file; never claim to replace a CPA.
Never fabricate deduction eligibilityDeductions carry confidence levels, not guarantees.
Focus on planning instead of filing
Updateable tax-year configurationTax-year data is configurable, not permanently hardcoded.

Core modules · 13

Authentication and Workspace
Sign-up, login, workspaces, personal and business profiles, saved simulations, and advisor access.
Tax Profile Setup
Capture filing status, state, dependents, entity type, and business details.
Guided Intake Engine
Step-by-step flow with dynamic questions that avoids confusing tax terminology.
Deduction Discovery Engine
Simple questions surface personal and business deductions the user may be missing.
Tax Calculation Engine
Estimates federal, self-employment, taxable income, quarterly, effective, and marginal figures from configurable tax-year data.
State Tax Layer
Configurable state estimation covering no-income-tax and flat-tax states.
Scenario Simulator
Duplicate and compare scenarios like standard vs itemized or sole proprietor vs S-corp.
Quarterly Tax Planner
Estimated quarterly payments, safe reserve percentage, due dates, and underpayment warnings.
Tax Savings Meter
Shows estimated savings from retirement, HSA, home office, mileage, and business expenses.
Deduction Confidence Layer
Labels deductions from high confidence to CPA review recommended, never guaranteeing eligibility.
CPA Report Generator
Clean reports with income, expenses, deductions, burden, assumptions, and CPA questions, exportable to PDF.
Document Checklist Generator
Builds a checklist of W-2s, 1099s, receipts, mileage logs, and other records.
AI Planning Assistant
Explains calculations, deductions, and reserves without giving legal advice or guaranteeing deductions.

How it works

Choose what you're estimating
Select the tax year
Select your state
Enter your income types
Identify deductions that may apply
Identify credits that may apply
Enter business expenses
Enter withholding and payments already made
Review the estimate
Generate the report

Key screens

Personal Tax SimulatorEstimates federal, state, and self-employment tax from personal income and deductions.
Business Tax SimulatorEstimates business burden, deductible expenses, and quarterly payments by entity type.
Personal + Business CombinedCombines W-2 and business income into one estimate with withholding gap.
Scenario ComparisonSide-by-side burden comparison like standard vs itemized or W-2 vs self-employed.
Quarterly Tax PlannerQuarterly payments, reserve percentage, and underpayment warnings.
Tax Savings MeterEstimated savings and confidence per deduction.
CPA ReportCPA-ready summary with assumptions, opportunities, and review questions.
Document ChecklistGenerated list of records to gather for filing.

Data model

User
Workspace
WorkspaceMember
TaxProfile
BusinessProfile
IncomeEntry
ExpenseEntry
DeductionEntry
TaxScenario
ScenarioResult
TaxReport
ReportShareLink
AuditLog

Screens · 11

Tax Burden Simulator Command Center for Demo Holdings showing estimated tax liability $103,147, potential savings, entity performance by entity, and upcoming quarterly deadlines. — Command center

Tax Burden Simulator Entity Portfolio with three entity cards (Personal, Summit Consulting LLC, Harbor Real Estate LLC) each showing gross income, estimated tax, and effective rate. — Entity portfolio

Tax Burden Simulator Tax Reduction Lab showing $1,419 total potential savings, an offline-mode AI briefing, and a Fund a Health Savings Account strategy card. — Tax reduction lab

Tax Burden Simulator new-estimate wizard, step 1 of 5 (The basics): filing status, state, tax year, and dependents fields with a live estimate panel showing $22,228. — Estimate wizard step 1

Tax Burden Simulator new-estimate wizard step 1 of 5 (The basics) with filing status, state, tax year, and dependents fields and a live estimate side panel. — Estimate wizard step 1

Tax Burden Simulator wizard step 2 of 5 (Your income): income-type entries for W-2 wages and investment gains with amount and withholding fields, plus an Add income button. — Estimate wizard step 2 (income)

Tax Burden Simulator wizard step 3 of 5 (Deductions) with a mortgage-interest deduction entry and Add deduction, comparing itemized against the standard deduction. — Estimate wizard step 3 (deductions)

Tax Burden Simulator wizard step 4 of 5 (Payments) with an estimated-payments field and a checkbox to apply the simplified QBI deduction. — Estimate wizard step 4 (payments)

Tax Burden Simulator wizard step 5 of 5 (Your estimate) showing estimated total tax $22,228, a donut chart of where income goes, a tax breakdown, and a quarterly plan. — Estimate wizard step 5 (result)

Tax Burden Simulator Income page listing income sources (W-2 wages, investment gains) with totals for estimated tax, refund, gross income, and federal tax withheld. — Income sources

Tax Burden Simulator Deduction discovery page estimating $2,520 saved from a mortgage-interest deduction and a grid of common deductions the user might be missing. — Deduction discovery

How it is built

A Next.js app with PostgreSQL via Prisma and Auth.js (email/password plus optional Google sign-in). The tax and deduction logic runs server-side against configurable tax-year data; Anthropic Claude powers an optional AI assistant with a deterministic fallback; React-PDF generates reports; Upstash Redis provides rate limiting; Resend sends email; Sentry monitors errors. S3-compatible object-storage keys are wired for a deferred document-upload feature.