# THQT

> Free, browser-only tools and plain-English guides for GST invoicing and getting paid, for Indian small businesses and freelancers. Operated by Kartikeya Mishra, Lucknow, India.

All tools compute in the visitor's browser; nothing typed into them is transmitted or stored. Tax rates reflect GST 2.0, in force from 2025-09-22, last reviewed 2026-10-19. Every guide ends with the statutory provisions it relies on. Changes and corrections are dated at https://www.thqt.me/changelog.

Nothing on this site is tax or legal advice.

## Tools
- [GST invoice generator](https://www.thqt.me/tools/gst-invoice-generator): Build a Rule 46 tax invoice at the rates in force and print it or save it as a PDF. Works out CGST and SGST or IGST from the place of supply.
- [GST calculator](https://www.thqt.me/tools/gst-calculator): Add GST to a price or extract the GST already inside a total, at the GST 2.0 rates, with the tax split shown either way.
- [MSE payment deadline checker](https://www.thqt.me/tools/msme-payment-deadline-checker): See which payables to micro and small suppliers put your tax deduction at risk under section 43B(h) or section 37(2)(g).
- [Late payment interest calculator](https://www.thqt.me/tools/msme-late-payment-interest-calculator): Work out the statutory interest owed under section 16 of the MSMED Act, from the correct 15- or 45-day deadline.
- [GSTIN validator](https://www.thqt.me/tools/gstin-validator): Check a GST number’s pattern, state code and checksum. Catches typos before they reach an invoice.
- [Invoice number generator](https://www.thqt.me/tools/invoice-number-generator): Design a numbering series and check it against the sixteen-character limit and the characters Rule 46 permits.
- [Payment reminder writer](https://www.thqt.me/tools/payment-reminder-generator): Draft a reminder at one of three escalation levels, from a gentle nudge to a formal notice citing the statutory position.

## Guides
- [What GST 2.0 changed on your invoices](https://www.thqt.me/guides/gst-2-0-invoice-changes): From 22 September 2025 the main GST rates are 5% and 18%, plus 40% for a short list of luxury and sin goods. Most 12% items moved to 5% and most 28% items to 18%. For supplies that straddled the change, section 14 of the CGST Act decides the rate.
- [What a GST invoice must legally contain](https://www.thqt.me/guides/gst-invoice-rules): A GST tax invoice must carry sixteen particulars listed in Rule 46 of the CGST Rules, including a consecutive serial number under sixteen characters, the place of supply, HSN or SAC codes and the tax split. Unregistered suppliers and exempt supplies use a bill of supply instead.
- [The 45-day payment rule for small suppliers](https://www.thqt.me/guides/msme-45-day-payment-rule): Under the MSMED Act 2006, a buyer must pay a registered micro or small enterprise within the agreed period or 45 days from acceptance, whichever is earlier. Late payment attracts compound interest at three times the RBI bank rate, with monthly rests, as a statutory liability.
- [Invoicing international clients from India](https://www.thqt.me/guides/invoicing-international-clients): A service supplied to a client outside India, paid for in foreign exchange, is an export of services and is zero-rated. File a Letter of Undertaking once a year and you can invoice without charging IGST at all.
- [How to invoice a client so you actually get paid](https://www.thqt.me/guides/how-to-invoice-a-client): An invoice gets paid faster when it reaches the person who approves payment, states a specific due date rather than a period, lists a single unambiguous total, and includes the reference the client's system needs. Format matters less than routing.
- [Proforma invoice, quotation, tax invoice and delivery challan](https://www.thqt.me/guides/proforma-vs-tax-invoice): A quotation is an offer, a proforma invoice is a request for advance payment, a tax invoice is the document that creates the tax liability, and a delivery challan moves goods without a sale. Only the tax invoice triggers GST.

## Invoice formats by trade
- [Freelance web developer](https://www.thqt.me/invoice-format/freelance-web-developer): Web development is billed under SAC 998314 at 18% GST. Bill by milestone or by hour, and treat overseas clients as export of services rather than an ordinary inter-state supply.
- [Graphic designer](https://www.thqt.me/invoice-format/graphic-designer): Design services fall under SAC 998391 at 18% GST. Bill the design fee and any usage licence as separate lines, and cap revision rounds explicitly on the invoice.
- [Chartered accountant](https://www.thqt.me/invoice-format/chartered-accountant): Accounting and audit services are billed under SAC 998222 at 18% GST. Keep statutory fees paid on the client behalf out of your taxable value by billing them as a pure agent recovery.
- [Photographer](https://www.thqt.me/invoice-format/photographer): Photography is billed under SAC 998383 at 18% GST. Separate the shoot fee, the post-production and the image licence, and put travel and assistant costs on their own lines.
- [Interior designer](https://www.thqt.me/invoice-format/interior-designer): Interior design is billed under SAC 998391 at 18% GST, but the place of supply is where the property is located, not where your client lives.
- [Tutor or coaching centre](https://www.thqt.me/invoice-format/tutor-and-coaching): Coaching and private tuition is billed under SAC 999293 at 18% GST. The education exemption covers recognised institutions delivering a curriculum leading to a recognised qualification, which is narrower than most coaching centres assume.
- [Goods transporter](https://www.thqt.me/invoice-format/transporter): Goods transport is billed under SAC 996511, and for a goods transport agency the tax is frequently payable by the recipient under reverse charge rather than by you.
- [Construction contractor](https://www.thqt.me/invoice-format/construction-contractor): Construction is billed under SAC 995411 as a works contract, which is a supply of service even though it includes materials. Bill through running account bills against measured work.
- [Digital marketing agency](https://www.thqt.me/invoice-format/digital-marketing-agency): Marketing services are billed under SAC 998361, and media buying under 998365, both at 18% GST. Ad spend recovered from the client is not your revenue and belongs on its own line.
- [Garment retailer](https://www.thqt.me/invoice-format/garment-retailer): Garments use HSN codes in chapters 61 and 62. From 22 September 2025 readymade garments are taxed at 5% up to ₹2,500 a piece and 18% above it, so one invoice can legitimately carry two different rates.
- [Restaurant or caterer](https://www.thqt.me/invoice-format/restaurant-and-catering): Restaurant service is billed under SAC 996331. The commonly applied 5% rate comes with input tax credit disallowed, which changes how you should price rather than just how you invoice.
- [Medical practitioner](https://www.thqt.me/invoice-format/medical-practitioner): Healthcare services by a recognised practitioner are exempt from GST, but cosmetic procedures, dietary supplements sold at the clinic and room rent above the notified threshold are not, so a mixed practice needs two document types.

## THQT, the product
- [Request an invite](https://www.thqt.me/invite): THQT is invoicing software that numbers invoices, applies the GST split and sends payment reminders. Invite-only at present.
- [Pricing](https://www.thqt.me/pricing)

## About and policies
- [About](https://www.thqt.me/about)
- [Contact](https://www.thqt.me/contact)
- [Privacy policy](https://www.thqt.me/privacy)
- [Terms and conditions](https://www.thqt.me/terms)

## Optional
- [Full text of every guide](https://www.thqt.me/llms-full.txt)