Question 1

How do I add GST vs remove GST?

Accepted Answer

Add GST (exclusive): tax = amount × rate/100, inclusive total = amount + tax. Remove GST (inclusive / reverse): exclusive = amount ÷ (1 + rate/100), tax = amount − exclusive. Pick the mode that matches whether your figure already includes GST.

Question 2

What GST rates does this calculator use?

Accepted Answer

Presets follow GST 2.0 (effective 22 Sep 2025): 0%, 5%, 18%, and 40%, plus leftover niche rates still in force — 0.25% (rough diamonds), 3% (gold/jewellery), 12% (some bricks/tiles), 28% (pan masala and tobacco until a later notification). The rate box is editable. Slabs can change; this is not an official rate chart.

Question 3

What is the difference between CGST, SGST, and IGST?

Accepted Answer

Intra-state supplies split GST equally into CGST and SGST (or UTGST). Inter-state supplies and imports use IGST at the full rate. The calculator applies that split only; it does not apply cess, reverse charge, or composition-scheme rates.

Question 4

Are invoice amounts uploaded?

Accepted Answer

No. Amount, rate, add/remove mode, and intra/inter split run in your browser. Nothing is sent to ToolPetal.

GST calculator