Check whether an Indian GSTIN is valid (format, state code and checksum) and decode its state, PAN and entity type. Works offline; it does not confirm the registration is active on the GST portal.

Calculate GST for one or more line items. Works out intra-state (CGST+SGST, or CGST+UTGST in UTs) vs inter-state (IGST) from the supplier state and place of supply, handles GST-inclusive prices, cess and round-off, and gives the total in words.

Generate a GST-compliant tax invoice as a PDF on the user's computer (supplier and buyer details, HSN/SAC, tax split, place of supply, reverse charge, amount in words, bank/UPI details). Returns the file path and the tax breakdown. Ask the user for any missing supplier or buyer details instead of inventing them.

Find HSN codes (goods) or SAC codes (services) from the GST portal's official HSN/SAC master list, by everyday description ("laptop", "ghee", "CA services") or by code prefix. Works offline. Returns official descriptions with their chapter and heading. For the GST rate of goods, pass the code to find_gst_rate. Choosing the right classification is the user's responsibility: show the candidates, explain the differences, and suggest confirming with their CA when it is unclear.

Check whether an HSN or SAC code exists in the GST portal's official list, and get its description, the chapter and heading it sits in, and its sub-codes. For a code that isn't listed, returns the nearest valid parent code and its sub-codes. Works offline. For the GST rate, use find_gst_rate.

Official GST rates for goods, from the Gazette of India: Notification 09/2025-Central Tax (Rate) (rate schedules) and 10/2025-Central Tax (Rate) (exemptions), with every amendment up to the latest checked date applied (e.g. tobacco to 40% from 1 Feb 2026, psyllium exempt from 1 Nov 2026). Give an HSN code (4-8 digits) to get every entry that covers it, with the rate, CGST/SGST/IGST split, the notification and serial number, and the entry's exact wording; or give a product description to search the notifications' own wording. Several entries can cover one code with different rates: explain the conditions to the user rather than picking silently. Services (SAC 99xxxx) are not covered yet. Works offline.

Convert a rupee amount to words in the Indian numbering system (lakh, crore), as used on invoices and cheques.

Decode bank-statement UPI narrations (e.g. 'UPI/DR/412345678901/SWIGGY/YESB/swiggy@ybl/Payment') into payee, VPA, app/bank, UTR/RRN reference and direction. Accepts up to 500 lines at once.

Analyse an Indian bank statement locally: spending by category (food delivery, groceries, travel, bills, EMI, investments...), month-by-month in/out, top payees, largest spends, recurring payments and subscriptions, and UPI usage. Provide file_path to a PDF or CSV statement from net banking (SBI, HDFC, ICICI, Axis, Kotak and other layouts are detected automatically; password-protected PDFs need password), or pass transactions directly. Every PDF row is checked against the running balance. Data never leaves the computer.

Convert a PDF (or CSV) bank statement into a clean CSV that opens in Excel or Google Sheets: one row per transaction with date, narration, reference, debit, credit, balance, plus category, payee and decoded UPI details. Rows are checked against the running balance, and the result reports any that don't agree. Runs locally.

Find the bank, branch, address, MICR and supported payment modes (UPI/IMPS/NEFT/RTGS) for an IFSC code.

Find the district, state and post offices for an Indian 6-digit PIN code.