How Hms works

Hms ("How many subscriptions") adds up what you pay every month for AI tools such as ChatGPT, Claude, Gemini, Perplexity, Cursor and GitHub Copilot, and shows the total in your own currency. It covers more than 60 services across chat assistants, coding tools, image and video generators, voice and music tools, and developer platforms.

Who it is for

• People who signed up for several AI tools over time and want to see the real monthly and yearly cost in one place.
• Anyone paying in won, yen, euros or another currency for services that are priced in US dollars.
• Freelancers and small teams who want a quick list of which tools renew on which day of the month.

How to use it

1. Add a subscription. Press Add AI subscription, find the service by name or category, and choose your plan from the dropdown.
2. Match what you actually pay. Each plan starts with its list price in USD. Change it if you pay a different amount, for example a regional or annual price.
3. Add discounts and billing days. Back on the main view, enter a discount percentage for a plan and the day of the month it renews. Hms shows the next payment date and how many days are left.
4. Pick your currency. Choose a currency, set the exchange rate for 1 USD, and turn the 10% tax on or off.
5. Get reminders. Press Remind to add each billing day to Google Calendar as a monthly repeating event.

How the total is calculated

For each subscription Hms takes the monthly USD price, applies your discount, adds tax if it is switched on, and converts the result with your exchange rate:

monthly cost = USD price × (1 − discount %) × 1.10 (tax) × exchange rate

The yearly figure is the monthly total multiplied by 12. For example, a USD 20 plan with no discount, 10% tax and a rate of 1,400 KRW per USD comes to 20 × 1.1 × 1,400 = ₩30,800 a month, or ₩369,600 a year.

The 10% tax option exists because South Korea charges 10% value-added tax on digital services that overseas companies sell to consumers in Korea, and many AI services list their prices before that tax. Other countries use different rates, so switch the option off if it does not apply to you. Your card company may also add a foreign transaction fee; check your card's terms, as Hms does not include it.

Ready to try it? Open the calculator, or read the frequently asked questions.