Built for Precision.
Designed for Everyone.
We build high-accuracy tax calculation tools that work instantly in your browser — no signups, no data collection, no complexity.
with 2026 rates
VAT / GST presets
supported
ever stored
Our Story
Why We Built This
Reverse Tax Hub was founded to address a systemic deficiency in financial web tooling: slow, bloated, and ad-ridden calculation interfaces that consistently return inaccurate results for combined state and local tax rates.
In an era where financial precision is paramount — for freelancers separating tax from invoices, for e-commerce sellers verifying nexus obligations, for travelers comparing prices across borders — we recognized that users were relying on outdated legacy tools. Many of these tools used stale rate tables, rounded incorrectly, or simply did not account for local county add-ons at all.
We designed our engine from the ground up using edge-compiled static builds and client-side instant computation. Our architecture guarantees sub-millisecond calculation updates, zero layout shift, and complete financial privacy by ensuring all computational logic remains on the user's device — never transmitted to any server.
Our Mission
Three Core Principles
Precision
We use high-precision decimal arithmetic — not floating-point shortcuts — to eliminate rounding errors in every calculation. Every rate is cross-referenced against official government sources before being published.
Performance
All calculations execute in zero network round-trips. Our calculator responds as you type, with no loading spinners, no API calls, and no delays — even on slow connections or older devices.
Privacy
Every value you enter stays in your browser tab. We store nothing. We log nothing. Your financial inputs are never transmitted, indexed, or associated with your identity in any way.
Data Standards
How We Source & Verify Rates
Accuracy is the cornerstone of our platform. All rates preloaded into our calculators go through a four-step verification process before being published.
- 01
Primary Source Retrieval
US state rates are pulled directly from each state's Department of Revenue official publications and statutory schedules. Global VAT/GST rates are sourced from local tax authority publications and central government gazettes.
- 02
Cross-Reference Verification
Each rate is independently cross-referenced against at least two authoritative sources — including the Tax Foundation, OECD revenue statistics, and official government APIs where available.
- 03
Legislative Change Monitoring
We track pending state legislature bills, federal tax authority announcements, and OECD updates. When a change is confirmed, we update the rate database before the effective date.
- 04
Quarterly Audit Cycle
Our entire rate database undergoes a full audit every quarter. All 50 US states and 50+ global jurisdictions are reviewed against the latest official publications to ensure 2026 compliance.
The Team
Who We Are
Reverse Tax Hub is a distributed team of software engineers, chartered accountants, and taxation policy specialists. We are united by the belief that complex financial mathematics should not require complex software.
Our contributors have experience working in corporate tax compliance, e-commerce financial infrastructure, open-source tooling, and international VAT advisory roles. This unique combination of regulatory knowledge and technical rigour shapes every decision we make — from the formulas we implement to the way we present results to users.
We intentionally keep our codebase lean: no databases, no user accounts, no analytics cookies. This is not just a privacy commitment — it also means the tool loads faster, costs less to operate, and has fewer attack surfaces.
Engineers
Full-stack & performance specialists
Tax Advisors
CPA & international VAT experts
Researchers
Rate monitoring & verification
Common Questions
About the Platform
Have a question, found a rate error, or want to suggest a feature? We read every message.
Blog & Guides →In-depth articles on US sales tax, global VAT, and how to use reverse-tax math in real life.
Privacy Policy →Full details on what we collect (very little), how we use it, and your rights.