Add up your balances from your account statements. You should be able to get the year end balances from the brokers.
As a side comment, form 5498 is almost always issued late, because of the ability to make retroactive contributions means your 2025 contributions are not final until after April 25, 2026. But once the form is available it is a good idea to download a copy and keep it with your other tax papers in case you ever need to prove your contributions or the source of your funds.