GSTR-1 Calculator
Total up your outward supplies into GSTR-1-style figures before filing.
Add your outward supply lines for the period. The totals mirror how they flow into GSTR-1 (B2B/B2C taxable value split by tax head).
Enter at least one supply line to build your GSTR-1 estimate.
How the calculation works
GSTR-1 reports what you sold. This estimate totals your outward supply lines the same way the return does — taxable value and tax split by head.
- Per line
Taxable value × Rate ÷ 100 = tax for that line's head - Return totals
Σ Taxable values; Σ CGST; Σ SGST; Σ IGST - Invoice value
Taxable value + Total tax (what buyers actually owe you)
Worked example
A month with one local B2B sale and one inter-state sale.
You enter
You get
Important points to keep in mind
- Real GSTR-1 also splits B2B vs B2C-large vs B2C-small tables — this gives the headline numbers to check against.
- Advances received and credit/debit notes adjust these totals in their own sections.
- Use GSTSelf's full GSTR-1 preparation flow to build and file-ready JSON once figures look right.
Frequently asked questions
What is GSTR-1 in one line?
The monthly/quarterly statement of all your outward supplies — everything you invoiced, with buyer details where applicable.
Do exempt sales appear here?
Yes, in Table 8 (nil-rated/exempt), though they carry no tax. This tool focuses on taxed supplies.
How close is this to the real return?
It reproduces the arithmetic of the summary tables. Invoice-level details (buyer GSTINs, HSN codes) still need entering in the actual workflow.
Related GST tools
Prepare your returns in GSTSelf
Done estimating? Prepare the actual return.
GSTSelf walks you through your invoices, builds GSTR-1 and GSTR-3B data, and keeps everything on your device — no uploads, no account.