According to an embodiment, a device includes a table creator, an estimator, and a dictionary creator. The table creator is configured to create a table based on similarity between distributions of nodes of speech synthesis dictionaries of a specific speaker in respective first and second languages. The estimator is configured to estimate a matrix to transform the speech synthesis dictionary of the specific speaker in the first language to a speech synthesis dictionary of a target speaker in the first language, based on speech and a recorded text of the target speaker in the first language and the speech synthesis dictionary of the specific speaker in the first language. The dictionary creator is configured to create a speech synthesis dictionary of the target speaker in the second language, based on the table, the matrix, and the speech synthesis dictionary of the specific speaker in the second language.