Synonyms to that is

actual, absolute, admitting no question, as is, ascertained, attested, authentic, authenticated, being, bona fide, categorically true, certain, certified, commonplace, concrete, confirmable, confirmed, contemporaneous, contemporary, corroborated, current, de facto, demonstrable, demonstratable, demonstrated, determined, documentary, effectual, established, everyday, existent, existing, extant, factual, for real, fresh, genuine, hard, historical, honest-to-God, immanent, immediate, inappealable, incontestable, incontrovertible, indisputable, indubitable, instant, irrefragable, irrefutable, latest, legitimate, manifest, material, modern, new, not in error, objective, objectively true, ordinary, phenomenal, physical, positive, present, present-age, present-day, present-time, provable, proved, real, realistic, realized, routine, running, self-evident, solid, substantial, substantiated, sure-enough, tangible, testable, that be, topical, true, true as gospel, true to life, truthful, unanswerable, unconfutable, unconfuted, undeniable, undenied, undoubted, unerroneous, unfallacious, unfalse, unimpeachab