Official Sources & References
Tax Calculation Sources
Complete directory of official tax authority resources used for all tax calculations on our platform. All calculations are based on 2026 tax laws and regulations published by government tax authorities.

Last Updated: January 16, 2026

We update our references annually to reflect the latest tax law changes.

15 Countries
United States
Internal Revenue Service (IRS)
Canada
Canada Revenue Agency (CRA)
United Kingdom
HM Revenue & Customs (HMRC)
India
Income Tax Department, Government of India
Australia
Australian Taxation Office (ATO)
Germany
Bundesfinanzministerium (Federal Ministry of Finance)
France
impots.gouv.fr (French Tax Administration)
Singapore
Inland Revenue Authority of Singapore (IRAS)
Japan
National Tax Agency
Brazil
Receita Federal (Federal Revenue)
Malaysia
Lembaga Hasil Dalam Negeri (LHDN)
Philippines
Bureau of Internal Revenue (BIR)
Belgium
FOD Financiën (Federal Public Service Finance)
Hong Kong
Inland Revenue Department (IRD)
Malta
Commissioner for Revenue (CFR)
About Our Sources

Accuracy & Transparency

All tax calculations on our platform are based exclusively on official government publications and tax authority resources. We cite our sources transparently to ensure you can verify our calculations and trust our results.

Annual Updates

Tax laws and rates change annually. We review and update all references at the beginning of each tax year to ensure our calculators reflect the latest tax brackets, rates, and regulations published by official tax authorities.

Verification

We encourage users to verify calculations by consulting the official tax authority resources linked above. For complex tax situations or official tax filing, please consult with a qualified tax professional.