Live demo

See where the models disagree.

This is a real example of what ReliableAI surfaces. We ran this question through Claude, GPT, Gemini and Grok simultaneously — and the differences are exactly where the analysis gets interesting.

Query submitted
"What is the current corporate tax rate in the United States, and how does it compare to the EU average?"
Claude Sonnet

The US federal corporate tax rate is 21%, established by the Tax Cuts and Jobs Act of 2017. ✓×4

When including state and local taxes, the combined effective rate typically ranges from 25–28% depending on the state, with California reaching up to 29.84%. ⚡Único

The EU average corporate tax rate sits around 21.3%, making the US federal rate roughly at parity with the EU average, though this varies significantly by member state.

GPT-4o

The federal US corporate tax rate is 21%, unchanged since the 2017 tax reform. ✓×4

The EU's weighted average corporate tax is approximately 19.7%, meaning the US federal rate is modestly higher than the EU average on a headline basis. ⚔

It's worth noting that the effective tax rate paid by large US corporations, after deductions and credits, is often considerably lower than the statutory 21%. ⚡Único

Gemini Pro

The US corporate tax rate is 21% at the federal level. ✓×4

The EU average varies by source, but according to the European Commission, the statutory average across EU member states is closer to 21.8%, making the US and EU rates nearly identical. ⚔

Ireland (12.5%), Hungary (9%), and Bulgaria (10%) are notable outliers that significantly pull down EU averages in some calculations. ⚡Único

Grok 3

21% federal corporate tax rate in the US, set in 2017. ✓×4

The Biden administration has proposed raising this to 28%, and global minimum tax discussions under OECD Pillar Two (15% minimum) may affect comparisons going forward. ⚡Único

The EU average depends heavily on whether you use simple or GDP-weighted averages — the range cited in research goes from 19.5% to 22%, making direct comparison nuanced.

⚔ Contradiction detected: GPT-4o cites the EU average as 19.7% (US higher than EU). Gemini cites 21.8% (near parity). Claude cites 21.3% (at parity). This discrepancy stems from different methodologies — simple average vs. GDP-weighted average — and reflects a genuine ambiguity in how the EU figure is measured. This is exactly the kind of divergence a single-model answer would hide.
⚗ Integrated Synthesis · Claude Opus

The US federal corporate tax rate of 21% is unambiguous and agreed upon by all four models. The comparison with the EU average, however, requires methodological precision.

The apparent contradiction between models (19.7%–21.8% EU average) resolves when accounting for measurement method: simple average across EU member states yields ~21.3–21.8%, while a GDP-weighted average (which gives more weight to Germany, France) produces ~19.5–20%. Both figures are cited in reputable sources.

The most defensible conclusion: at the federal level, the US rate (21%) is broadly comparable to the EU average, with the precise difference depending on methodology and the inclusion of tax havens like Ireland and Hungary. For business decisions requiring cross-jurisdictional comparisons, effective rates (post-deductions) are more meaningful than statutory headlines.

78% confidence Contradiction resolved · 4 models · Hallucination risk: Low
✓×4 Point agreed by all models ⚡Único Unique insight from this model ⚔ Potential contradiction detected Consensus paragraph Unique paragraph

Your turn. Run your own question.

Free plan · No credit card · Claude, GPT, Gemini and Grok in parallel

▶ Start researching free

Or go back to explore more.