Sources & methodology
TaxToolSet is designed around traceable rules rather than opaque formulas. A live numeric tool should have enough source context to explain why a rate or threshold applies.
Source hierarchy
- Primary legislation, enacted finance laws and official schedules.
- Official authority notifications, circulars, valuation rulings and rate cards.
- Official portals, tariff databases and published guidance.
- Secondary material only as supporting context, not as the sole basis for a published numeric rule where an official source is required.
Versioning
Tax rules change over time. Published rule sets are treated as period-specific records. A new law or rate should create a new effective version rather than silently changing the historical rule.
Page updates and tax-rule periods
Page updates, source publication dates and tax-rule effective periods describe different things. A page or interface update does not by itself mean that a tax rule has changed or that a new legal review has taken place. Source links and the period shown on each tool should be checked for the intended calculation.
When TaxToolSet will not guess
If the platform cannot establish a current numeric rule with sufficient confidence, it may show the source, ask for a user-supplied verified value, or keep the tool non-indexable until the source issue is resolved.
Corrections
Tax law can change quickly. Please report possible errors through the contact page. Include the authority, source link or legal reference where possible.