Calculate Goods and Services Tax precisely and instantly, right in your browser — free, with no sign-up and nothing sent to a server.
Last updated: July 14, 2026
This tool is for general informational purposes only and isn't tax or financial advice. Confirm the applicable rate with FBR or a qualified tax professional before invoicing or filing.
Back to WebTools5A GST (Goods and Services Tax) calculator works out how much tax should be added to, or is already baked into, the price of something. GST is a consumption tax charged at each stage a product or service moves through the supply chain, and doing that math by hand — especially across several line items or invoices — is exactly the kind of repetitive task that's easy to get slightly wrong. This calculator takes the percentage math off your plate: type in an amount, pick a rate, and it hands back both the tax figure and the tax-inclusive total.
The rate presets here are the ones most commonly referenced for Pakistan, but the arithmetic behind GST and VAT is the same everywhere a percentage-based consumption tax applies. Because governments revise these rates periodically, treat the presets as a convenient starting point rather than a guaranteed current figure — more on that below.
This calculator is a convenience tool, not tax advice. Rates, exemptions, and rules change, and the correct rate for your specific goods or services can depend on details this simple tool has no way of knowing. For anything going into an invoice, tax return, or compliance filing, cross-check the current rate with FBR or a qualified tax professional.
Using this GST calculator takes three steps:
No sign-up, no downloads, and the result updates instantly every time you change the amount or rate and recalculate.
This is where a lot of manual GST math goes wrong, so it's worth spelling out clearly. This calculator works in one direction: you give it a pre-tax (exclusive) amount, and it adds GST on top to give you the total. That's the right approach when you're quoting a price and need to show the tax separately.
Sometimes you have the opposite problem — you already know the final, tax-inclusive total (say, from a receipt) and need to figure out how much of that was GST. The formula for that is a little different from simply multiplying by the rate, because the rate applies to the pre-tax amount, not the total:
GST amount = Total × (rate ÷ (100 + rate))
Pre-tax amount = Total − GST amount
For example, on a total of PKR 1,180 at an 18% rate: GST = 1180 × (18 ÷ 118) ≈ PKR 180, and the pre-tax amount comes out to PKR 1,000. Keep that formula handy if you ever need to reverse-engineer a receipt total.
Manual percentage math is fine for a single transaction, but it gets error-prone fast once you're doing it repeatedly across an invoice batch, a pricing sheet, or a stack of receipts. A calculator removes the arithmetic risk entirely and gives you a consistent, repeatable result every time.
Businesses use this for invoicing and quick pricing checks. Shoppers use it to see the real final cost of something before checking out. Freelancers use it to work out tax-inclusive quotes for clients. None of that requires an account, an installed app, or your numbers leaving your device.
| Preset | Typically used for |
|---|---|
| 18% | General goods and services category |
| 17% | Standard-rated category |
| 16% | Reduced-rate category |
| 0% | Exempt or zero-rated items |
Need other quick math while you're here? Our Scientific Calculator handles everything from basic arithmetic to trigonometric functions, and the Age Calculator is useful for date-based calculations.
Type the pre-tax amount into the input field (e.g., 1500.00).
Select the applicable GST rate from the dropdown menu.
Click Calculate and instantly see the GST amount and total including tax.
No. Every calculation runs directly in your browser using JavaScript. The amount and rate you enter are never transmitted anywhere.
That depends on the goods or service in question and the current rules where you're filing. This tool ships with common preset rates, but tax rates are set by the government and can change, so confirm the applicable rate with FBR or a qualified tax professional before invoicing or filing.
It's built around Pakistan's commonly referenced GST rate presets, but the underlying math works for any percentage-based consumption tax, including VAT in other countries. You can treat the rate dropdown as a starting point and adjust your thinking to your own jurisdiction's rate.
This calculator adds GST on top of the amount you enter, so you should type in a pre-tax (exclusive) figure. If you already have a tax-inclusive total and need to work backward to find the tax portion, see the GST-inclusive vs GST-exclusive section on this page for the formula.
Yes, mathematically GST and VAT calculations work the same way — a percentage applied to a base amount. Just make sure you're using the correct VAT rate for your country rather than the Pakistan-oriented presets.
The calculation itself is exact; the display is rounded to two decimal places, which matches how most currencies and invoices are presented.
No installs, no browser extensions, no account. Enter an amount, pick a rate, and read the result.
Yes. There's no usage cap, no premium tier, and no fee to use the calculator as many times as you need. More questions? Our full FAQ page covers the rest of the toolkit.