Everything to research a tax question, in one place
A case-law library, 40 calculators and 110+ guides, all written or reviewed by CA Prabhakar Kumar, FCA, and free to use. Pick a tool, or start from a topic below.
Knowledge Hub
Three tools, one author
Built for taxpayers, business owners and professionals who want to understand the position before they act.
2,200+
Judgments & circulars
TaxSphere library
Income tax case law organised by court, section and subject. Plain-English summaries with the source for every entry.
Explore TaxSphere →40
Calculators
Tax & finance calculators
Income tax, HRA, capital gains, TDS, GST, advance tax, 234A/B/C interest, F&O, crypto, EMI, SIP and more.
Open calculators →110+
Guides
Insights & guides
Plain-language guides on ITR, tax planning, GST, capital gains and business setup, updated for the Income-tax Act, 2025.
Read insights →By topic
Start from your situation
Income tax notices
- Assessment-stage rulings
- Section index
- Validity tracker
- 234A/B/C interest calculator
- Worked examples
Next step
Research done? Get it reviewed.
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