Calculators that answer the first question.
GST split, channel cost and migration effort. No email gate. No sales call.
No signup
Runs in your browser. Nothing is stored.
CGST / SGST or IGST
Voice + WhatsApp + email
The short version
- This build ships two calculators, not three: a GST split and an AI channel overage estimate. Both run entirely in the browser, with no signup, no email gate and no storage of what you type.
- The GST tool takes a taxable amount and a supply type, then shows 9% CGST plus 9% SGST for an intra-state supply or 18% IGST for an inter-state one. It assumes a single 18% rate and does not decide your place of supply.
- The channel tool subtracts the Growth allowances — 1,500 voice minutes, 5,000 WhatsApp marketing messages and 1,00,000 emails — and prices only the excess at ₹2.20 a minute, ₹1.15 a message and ₹0.03 an email.
- Neither tool includes 18% GST, the subscription itself, AI tokens, verification, utility WhatsApp messages or seats. Treat the output as a first estimate, not a quote.
- The page copy also mentions a migration effort calculator. It is not in this build, and this page describes what such an estimate would have to ask rather than pretending it exists.
- Both calculators are static JavaScript over fixed formulas. No model is involved, and the arithmetic is the same every time you load the page.
Why a calculator beats a contact form
Most pricing pages answer a question nobody asked yet. They list tiers, allowances and per-unit rates, and then ask for a work email before showing the one number the visitor came for. The result is a form fill from someone who has not decided anything, followed by a sales sequence that arrives before the person has finished reading. A calculator inverts that: it answers the arithmetic question immediately and lets the buyer decide whether the answer is interesting.
The two tools here cover the questions that actually arrive in the first conversation. What does 18% GST look like split across CGST and SGST, and what changes if the buyer is in another state? And if we send more than the plan includes, what does the excess cost per month? Both are questions with a definite answer, which is why they can be answered without a person.
There is no email gate, no account, and no analytics event tied to the numbers you type. The calculators are a few dozen lines of JavaScript that read inputs and write formatted rupees into the page. They run the same on a phone in a metro and on a laptop behind a bank firewall, and they keep working if the rest of the site is slow.
What the GST calculator actually does
The first tool takes one number and one choice. The number is the taxable amount in rupees, defaulting to ₹10,000. The choice is whether the supply is intra-state, which produces CGST at 9% and SGST at 9%, or inter-state, which produces IGST at 18%. It then shows the four lines a buyer expects to see on a quotation: CGST, SGST, IGST and the total including tax.
The arithmetic is deliberately visible. For an intra-state supply of ₹10,000 the tool shows ₹900 CGST, ₹900 SGST, ₹0 IGST and a total of ₹11,800. Switch to inter-state and the CGST and SGST lines fall to zero while IGST becomes ₹1,800 and the total stays the same. That is the whole model: 18% of the taxable value, split one way or the other, with the total invariant.
It does not compute anything else. There is no reverse calculation from a tax-inclusive price, no per-line rounding, no cess, no reverse charge, no TDS and no filing output. If you have a customer-facing price of ₹11,800 and need the taxable value, the tool will not do the division for you. That limit is worth stating plainly, because a calculator that looks authoritative is often trusted for things it was never built to do.
Intra-state or inter-state is a legal question, not a dropdown
The calculator asks you to pick a supply type because it cannot know the answer. Under the GST framework, the tax splits into CGST and SGST when the supplier and the place of supply are in the same state, and becomes IGST when they are in different states. The dropdown is the output of a determination, not a substitute for one, and getting it wrong on an invoice is a filing error rather than a rounding error.
For services, the place of supply generally follows the location of the recipient, with exceptions for immovable property, events, transportation and a handful of other cases. For goods, it generally follows where the goods are handed over or moved. A supplier in Maharashtra billing a registered buyer in Karnataka is usually an inter-state supply. A supplier in Maharashtra billing a buyer in Maharashtra is usually intra-state, even if the buyer’s head office is elsewhere.
Two edge cases trip people up often enough to mention. A bill to one state and a ship to another is not automatically inter-state; the place of supply rules decide, not the delivery address alone. And a buyer with a GSTIN in a different state from the billing address needs the invoice to reflect the registered place of supply, not the courier destination. When the answer is unclear, the correct move is to ask a chartered accountant, not to try both options until the totals match.
What the GST tool assumes, and what it ignores
The single biggest assumption is the 18% rate. Most services bill at 18%, which is why the tool defaults to it, but goods and some services carry other rates, and a calculator that hard-codes one rate is only useful for the slice of invoices that use it. If your supply is taxed at a different rate, the percentages will be wrong even though the arithmetic is right.
The second assumption is that the amount you enter is exclusive of tax. Indian price tags are frequently inclusive, particularly in retail, and the tool does not strip tax out of an inclusive figure. To get the taxable value from an inclusive price, divide by 1.18 first, then enter the result. The third assumption is that there is one line item. A real invoice with ten lines and mixed rates needs per-line treatment and a rounding rule, and this tool does neither.
Rounding deserves a sentence of its own. The tool rounds each displayed figure to the nearest rupee, which is fine for a quotation and not always fine for an invoice, where the tax amount is computed on the taxable value and then rounded according to the invoicing system’s rule. Differences of a rupee look trivial until a reconciliation report disagrees by a rupee across two hundred invoices. The tool is a check on your understanding, not a substitute for your billing system.
What the channel calculator actually does
The second tool estimates overage, not spend. It takes three monthly volumes — voice minutes, WhatsApp marketing messages and emails — subtracts the Growth plan allowances of 1,500 minutes, 5,000 messages and 1,00,000 emails, and prices what remains at ₹2.20 per connected minute, ₹1.15 per marketing message and ₹0.03 per delivered email. If a volume is below the allowance, that line is zero rather than negative.
The choice of Growth as the baseline is deliberate and also a limitation. Growth is the plan most teams evaluate, with 25,000 marketing contacts, 1,00,000 emails, 5,000 WhatsApp messages, 1,500 voice minutes, 5M AI tokens, 10 agents, 10 workflows and 15 seats at ₹7,999 a month or ₹6,399 annual. A team on Starter has smaller allowances and would see more overage for the same volumes; a team on Scale has larger ones and would see less.
The output is a single number labelled estimated overage, which is exactly what it is. It does not include the subscription, the 18% GST on either the subscription or the overage, AI token consumption, email verification, utility or authentication WhatsApp messages, or seats. A team that reads the total as a monthly bill will underestimate it by the plan price, which is the most common misreading of the tool.
A worked example you can check by hand
Take a month with 3,000 voice minutes, 9,000 WhatsApp marketing messages and 1,50,000 emails. Voice overage is 3,000 minus 1,500, which is 1,500 minutes at ₹2.20, or ₹3,300. WhatsApp overage is 9,000 minus 5,000, which is 4,000 messages at ₹1.15, or ₹4,600. Email overage is 1,50,000 minus 1,00,000, which is 50,000 emails at ₹0.03, or ₹1,500. The tool reports ₹9,400.
Now add the plan. Growth is ₹7,999 a month, so the month costs ₹17,399 before tax, and ₹20,530.82 after 18% GST, which an invoice would round. That is the number a finance team needs, and it is two steps beyond what the tool shows. The tool is honest about being one step: it prices the excess, not the relationship.
The example also shows why the email rate looks trivial and is not. At ₹0.03 an email, the difference between 1,00,000 and 5,00,000 sends is ₹12,000 a month, which is more than a plan upgrade in some cases and less in others. The arithmetic is easy; the decision about which side of the allowance to sit on is the interesting part, and it is covered further down this page.
What the channel estimate leaves out
Four costs are missing, and each has a reason. The subscription is missing because the tool measures overage. GST is missing because adding 18% to an estimate invites people to compare it with a tax-inclusive competitor price, which is not a like-for-like comparison. AI tokens are missing because the tool has no input for agent volume, and inventing a default would be worse than omitting the line. Verification is missing because not every sender verifies addresses.
The WhatsApp line is the one most likely to mislead. The tool prices marketing messages at ₹1.15. Utility and authentication messages, which are the ones used for order updates and OTPs, are priced at ₹0.22 in the published overage table. A business that sends mostly utility messages will see a much lower bill than the estimate suggests, and a business that sends mostly marketing will see the number the tool shows. The tool does not ask which, because it has one WhatsApp input.
Voice has a similar definitional catch. The published rate is per connected minute, so a call that rings out and is never answered is not billed as a minute of conversation, though it may still consume platform capacity. The tool multiplies minutes as entered, which means the number you type should already be connected minutes. Teams that enter dialled minutes will overestimate, sometimes by a third.
Upgrade or pay overage: the arithmetic
There is a break-even between staying on a plan and paying overage, and it can be computed rather than argued. Moving from Starter to Growth costs ₹5,000 more a month at list price and adds 1,000 voice minutes, 4,000 WhatsApp marketing messages and 75,000 emails. Priced at overage rates, those added allowances are worth ₹2,200, ₹4,600 and ₹2,250 respectively, or ₹9,050 if you would genuinely use all three.
That means the upgrade pays for itself when you are close to consuming the extra allowance across more than one channel. It does not pay for itself if you are only exceeding on voice, where ₹5,000 buys roughly 2,270 minutes at the overage rate but the plan only adds 1,000. In that case the honest answer is to pay the overage or buy a voice-heavy arrangement, not to upgrade for features you will not use.
Two rules make this simpler in practice. The spend cap means the worst case is bounded, so an unexpected spike does not become an unbudgeted invoice. And overage never exceeds the pay-as-you-go rate for the same meter, which caps the penalty for guessing wrong. Together they turn a pricing decision into a reversible one, which is the only kind most teams should be making on a monthly cadence.
The migration estimate that is not built yet
The page copy promises three calculators: GST split, channel cost and migration effort. Two exist. The third does not, and rather than describe a button that is not there, this section describes the questions such an estimate would have to ask. Anyone planning a migration can use the list manually, and anyone who has done one will recognise why a single input box would be dishonest.
The first input is contacts, split by whether they are marketing contacts, suppressed or unsubscribed, because only the first group affects the bill. The second is templates, counted by channel and by language, since fourteen Indian languages across email and WhatsApp is a different job from one language. The third is automations: how many live journeys, how many steps, and how many have a human approval gate that has to be rebuilt rather than copied.
Then come the items that decide the timeline rather than the price: the WhatsApp number and who currently holds it, the suppression list and whether it is exportable, the domain reputation you are leaving behind, and the integrations attached to the old tool. The published note says migration is typically 48 hours done for you, and that figure assumes these items are ready. A migration estimate that ignored them would be a number, not an estimate.
How the page behaves without JavaScript
Both calculators are progressive enhancement in the narrow sense: the markup renders with default values, and the script recalculates on input. With JavaScript disabled, a visitor sees ₹10,000 producing ₹900 CGST, ₹900 SGST, ₹0 IGST and ₹11,800, and sees the channel tool’s defaults producing zero overage. The numbers are correct for the defaults and do not respond to typing.
That is a deliberate trade. Server-rendering every keystroke would mean a request per input, which is slower and leaks the numbers to a server that has no reason to see them. Rendering the defaults means the page is readable, indexable and usable as a reference even when scripts fail, which matters on the slow connections and locked-down browsers that a surprising number of Indian buyers still use.
Nothing is stored. There is no local storage, no cookie set by the calculators, and no event sent anywhere with the amounts you enter. If you reload the page, the defaults return. That is not a marketing promise; it is what the code does, and it is why the tools can be used with figures from a real quotation without a data processing question arising.
From estimate to an actual quote
An estimate becomes a quote when three things are known: the plan, the billing period and the tax treatment. The plan sets the allowance, the period sets whether the 20% annual discount applies, and the tax treatment determines whether the invoice carries CGST and SGST or IGST. All three are questions a human answers, which is why the calculators stop where they do.
The practical sequence is to run the channel estimate against a realistic month, add the plan price, add 18% GST, and compare that with what the same volumes cost today across separate tools. The comparison is usually less dramatic than a sales deck suggests and more useful, because it includes the migration work and the double-entry that disappears. A single bill is worth something, but it is not worth inventing a saving.
If the number is close, the free plan is the cheapest way to test the assumption: 1,000 contacts, 5,000 emails, 100 voice minutes, 250 WhatsApp messages, one agent and one workflow, no card. If the number is clearly favourable, the scoping call is about allowances and the spend cap rather than about price. Either way, the calculator has done its job by making the next question specific.
Frequently asked questions
Are the calculators really free?
Yes. There is no signup, no email gate and no trial that expires. Both tools are static JavaScript on a public page, and the formulas are fixed: 18% split as 9% CGST plus 9% SGST or 18% IGST, and overage at ₹2.20 a voice minute, ₹1.15 a marketing WhatsApp message and ₹0.03 an email above the Growth allowances. Nothing you type is stored or sent anywhere.
Why does the GST tool only use 18%?
Because most services bill at 18%, and a single-rate calculator is honest about being a single-rate calculator. Goods and some services carry different rates, and a supply with mixed line items needs per-line treatment that two inputs cannot express. If your rate is not 18%, the tool will not help, and using it anyway produces a confident wrong answer, which is worse than no answer.
Does the channel estimate include GST?
No. Every figure is exclusive of 18% GST, matching how the plans are priced. To get a tax-inclusive number, add 18% to the overage total and to the plan price separately, then add them. The tool deliberately does not do this for you, because a tax-inclusive estimate is easy to compare against a competitor’s exclusive price and draw the wrong conclusion.
Which plan does the cost calculator assume?
Growth, which includes 1,500 voice minutes, 5,000 WhatsApp marketing messages and 1,00,000 emails for ₹7,999 a month, or ₹6,399 on annual billing. The allowances are hard-coded for that plan. If you are on Starter, Scale or Enterprise, the estimate will be wrong in a predictable direction: too low for Starter, too high for Scale, and meaningless for a custom Enterprise allowance.
Why is my WhatsApp bill higher than the estimate?
Two likely reasons. The tool prices marketing messages at ₹1.15 and does not model utility or authentication messages at ₹0.22, so a mostly-marketing mix will match and a mostly-utility mix will come in lower. The other reason is volume timing: the estimate is monthly, while a campaign that fires 40,000 messages in three days can exhaust an allowance before the month is half over.
Can I use these numbers in a budget approval?
Use them as a first pass and label them as such. The channel estimate omits the subscription, GST, AI tokens, verification, seats and utility messages, so the real invoice is higher. For an approval, take the estimate, add the plan price, add 18% GST, and add a line for tokens and verification based on your own volumes. That produces a defensible range rather than a single number that will be contradicted by the first invoice.
What happened to the migration effort calculator?
It is named in the page copy but not implemented in this build, and we would rather say so than describe a tool that does not exist. The section above lists what such an estimate would need to ask: contacts by consent state, templates by channel and language, live automations, the WhatsApp number holder, the suppression list and the integrations attached to the old tool. You can work through that list manually today.
Do the calculators work without JavaScript?
They render with default values and correct arithmetic for those defaults, but they do not respond to typing. With scripts disabled you will see ₹10,000 producing ₹900 CGST and ₹900 SGST, and the channel tool showing zero overage for its defaults. That is intentional: the page stays readable and indexable, and no keystroke is sent to a server. Interactive use needs JavaScript enabled.
Where do the overage rates come from?
From the published pricing table: ₹2.20 per connected voice minute, ₹0.03 per delivered email, ₹1.15 per WhatsApp marketing message, ₹0.22 per utility or authentication message, ₹0.30 per thousand AI tokens on the mid-tier model, and ₹0.35 per email verified. The pay-as-you-go rates are ₹2.50 a minute and ₹0.05 an email, and overage is never billed above those.