Techniques for bidirectional text selection are disclosed. When a character selection is received, such as a “Shift+Arrow” input, the unanchored side of a selection area is adjusted by one glyph in the selection direction. The adjusted selection area is then evaluated in terms of logical indices that define the selection. If the range of logical indices is contiguous, such as the range {3, 4, 5}, then the adjusted selection area is accepted, although further adjustments are optionally made for glyphs that map to multiple characters. However, if the range of logical indices is noncontiguous, such as {3, 4, 6}, then the selection area is further adjusted until a contiguous selection of logical indices is achieved. For instance, a character corresponding to logical index {5} is added to a selection of characters corresponding to logical indices {3, 4, 6} to produce a selection that is logically and visually contiguous.