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Bending is how a diatonic harmonica plays the blues
A diatonic harmonica is tuned to one major scale, yet blues players use it to play notes that are not in that scale at all. The trick is bending: by changing the shape of the mouth and throat, a player lowers a reed’s pitch by one or more semitones, reaching the flat thirds, flat fifths, and flat sevenths that define the blues sound. Without bends, the harmonica would be a simple folk instrument; with them, it becomes one of the most expressive instruments in popular music.
The tool above charts every bend for any harmonica key. Pick a key and a hole, and it shows the blow note, the draw note, every bend on that hole with its frequency, and any overblow or overdraw. A second finder answers the reverse question: name a note, and it lists every hole and action that produces it.
Draw bends: holes one to six
Draw bends happen where the draw note sits higher than the blow note, which is holes one to six. Hole one bends once, from D down to D flat. Hole two bends twice, through F sharp to F. Hole three bends three times, through B flat and A to A flat, and it is the deepest, hardest bend on the instrument. Holes four, five, and six bend once each.
Each bend drops the note exactly one semitone further. That regularity is your friend: once you can hear semitone steps, you can aim for a specific bend rather than sliding vaguely downward. Use the tool’s frequencies with a tuner app to check whether your bend lands on the intended note.
Blow bends: holes eight to ten
Blow bends mirror draw bends at the top of the instrument, where the blow note sits higher than the draw note. Hole eight bends once, from E to E flat. Hole nine bends twice, through F sharp to F. Hole ten bends three times, through B and B flat to A. Hole seven, where blow and draw are close together, does not bend.
Blow bends feel different from draw bends and often come later in a player’s development, because the top holes are smaller and the embouchure is tighter. Practise them gently: forcing a blow bend with pressure usually chokes the reed instead of bending it.
Overblows and overdraws complete the map
Overblows on holes one to six and overdraws on holes seven to ten raise the draw note by one semitone, and they give the advanced player the remaining chromatic notes. Together with bends, they make every note of the chromatic scale available on a diatonic harmonica, which is why overblow technique transformed the instrument in recent decades.
Overblows demand a precise, narrow air channel and a harmonica with well-gapped reeds. Many players have their harmonicas adjusted for overblows, and beginners should not worry if overblows do not come at first. They are a destination, not a starting point, and the chart lists them for reference rather than as an immediate assignment.
How to practise bends without damaging reeds
Start on hole four draw, the easiest bend, and think of saying a long vowel that moves from “eee” toward “ahh” while drawing slowly. The pitch should drop smoothly, not jump. When it drops a semitone and holds steady, you have the bend. Practise holding it, then releasing back to the natural note, before moving to other holes.
Never force a bend with hard suction. Reeds are thin brass, and violent bending can fatigue them or pull them out of alignment. Gentle air, a relaxed throat, and short practice sessions protect both the instrument and your progress. If a bend will not come, try a different hole or a different harmonica before pushing harder.
Using the note finder
The finder is the practical heart of the tool. Suppose a song needs an F sharp on a C harmonica: the finder shows hole two draw bend one, and hole nine blow bend one, among others. Choose the option that sits near the notes around it, and your phrases will flow instead of jumping across the instrument.
That kind of planning is what separates players who hunt for notes from players who play melodies. Learn the bend chart for your harmonica’s key, practise one hole at a time, and let the blues notes arrive cleanly and in tune.