No app, no account, no spreadsheet. Five steps, then one number that makes the decision for you: what each thing costs over ten years.
Three places cover almost every recurring charge. Your bank and card statements for the last twelve months, searched for the same amount appearing monthly. Your phone's subscription list: on iPhone, Settings → your name → Subscriptions; on Android, Play Store → Payments and subscriptions. And PayPal, under Automatic payments, which is where the forgotten ones hide.
Write each one down with its price and billing date. Annual plans count: divide by twelve so everything is comparable.
This is the step most guides skip, and it is the one that decides things. Monthly prices are designed to feel small. Put your list into the Subscription Lifetime Receipt and it prints the yearly, five-year, ten-year and twenty-year totals as a receipt, plus what that money is in concrete things. Nothing you type is uploaded; the calculation runs in your browser.
Four options, not two. Keep if you used it in the last month and would miss it. Downgrade if you use it but not at the tier you pay for, which covers most music, cloud and streaming plans. Switch to annual only for things you are certain about, since annual saves 15 to 20 percent but locks you in. Cancel if you cannot remember the last time you opened it. Untick it in the calculator first and watch the ten-year line drop; that is usually enough.
"I will cancel it this weekend" is what the pricing model counts on. Cancel from the same list you used to find them. Most services keep your access until the end of the period already paid, so there is nothing to gain by waiting.
Six months from today, plus a reminder three days before any free trial ends. That single habit is worth more than the audit itself.
Not financial advice, and not an argument that subscriptions are bad. A service you use every week may be the best money you spend. The point is to decide with the ten-year figure in view instead of the monthly one, because they are the same purchase described two different ways.