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Paste a URL and see the result Google will build from it, trimmed to fit.
A search result is the site name and breadcrumb URL, the title in blue, and a snippet under it. Google builds the title from the <title> tag and the snippet from the meta description — not from og:title or og:description, which is why a page can share beautifully and still read badly in search.
Both are trimmed to fit the result width, and the snippet is often replaced entirely with text lifted from the page when Google decides that answers the query better.
Front-load the distinguishing words. Everything after the cut is lost on desktop and lost earlier on mobile, so a title that opens with the brand name spends its visible space on the part every one of your results already repeats.
The meta description is a suggestion rather than a contract. Write it as the one sentence you would want shown, then accept that Google will sometimes substitute its own.