Employees get a number every month that barely moves; freelancers get a number that swings from "great quarter" to "where did that invoice go" within six weeks of each other. A regular budgeting app assumes a steady paycheque landing on the same day, which is exactly the assumption that falls over the moment your income is lumpy. What actually helps isn't a stricter budget, it's a clear, ongoing view of what's coming in versus what's already spoken for (tax, mainly).
That last bit is the one freelancers skip and then regret at filing time: setting aside a rough percentage for tax the moment the money arrives, rather than after it's already spent on other things. Doing that well starts with keeping business spending separate from personal spending — even just logging expenses into two categories does most of the job. This tracker lets you do that without a bank login (you add expenses, or import a statement, and it stays in your browser) — no live business account required. Just try it against last month's invoices and see the split for yourself.