In 1840 he started a monthly magazine with Cornelius Mathews called Arcturus, which ran until 1842. He wrote articles on other authors while at home and in Europe. Between 1844 and 1846, Evert became the literary editor of John Louis O'Sullivan's The Democratic Review and United States Magazine, which moved from Washington D.C. to New York in 1840. In 1847 he became the editor of the Literary World, a weekly review of books written with his brother George Long Duyckinck until 1853. The two brothers were the unofficial leaders of the New York literary scene in the 1840s into the 1850s.
In 1854 the brothers were again united in the preparation of The Cyclopaedia of American Literature (2 vols., New York, 1855; enlarged eds., 1865 and 1875). He published Wit and Wisdom of Sydney Smith, with a memoir (New York, 1856); an American edition of Willroot's Poets of the Nineteenth Century (1858). Immediately after the death of Washington Irving, Duyckinck gathered together and published in one volume a collection of anecdotes and traits of the author, under the title of Irvingiana (1859); History of the War for the Union (3 vols., 1861'5); Memorials of John Allan (1864); Poems relating to the American Revolution, with Memoirs of the Authors (1865); Poems of Philip Freneau, with notes and a memoir (1865); National Gallery of Eminent Americans (2 vols., 1866); History of the World from the Earliest Period to the Present Time (4 vols., 1870); and an extensive series of Biographies of Eminent Men and Women of Europe and America (2 vols., 1873'4). His last literary work was the preparation, with William Cullen Bryant, of an edition of William Shakespeare. In January 1879, a meeting in his memory was held by the New York historical society, and a biographical sketch of Duyckinck was read by William Allen Butler.