Some chords can be quite a stretch to play on the piano. You simply can’t press all keys at once, even if you expand your hand as much as possible. Not everyone has hands like Franz Liszt or Sergej Rachmaninov that can span a 13th (tredecim). So how can you play chords that are too far for your hand?
I have a few solutions for you:
You can arpeggiate (“roll”) the chord. That means you play the notes sequentially from the bottom up (G, B, B, F, … in the example above) instead of hitting them at once. Use the pedal during that to let the notes ring together. Arpeggiating is always an option to play such “large” chords. To the ear of the listener it almost sounds the same as if the notes had been played simultaneously.
Large chords often appear under a fermata, at the end of piece or at another point of rest. This gives you time for the arpeggio. But even if that is not the case, you can arpeggiate in time — just make sure, that you start the arpeggio a little early and finish it on the beat.
It might be obvious to some, while others might not have considered it. You can experiment with fingering (which finger plays which key) in order to allow your hand to stretch further. In the example above, every pianist would play the two notes f and g in the right hand with just one finger — his thumb. This frees up the rest of your hand to stretch up to the fifth and ninth of the chord.
Stride Piano Style
This is kind of a special case of arpeggiating the chord. You play the bass note first and then hit the rest of the chord without arpeggiating. Be sure to hold down the sustain pedal to let it all ring together. This option might not work well in the example above, but it is a general strategy to play some large chords.
You should play the bass note slightly to early, so that you can hit the chord right on the beat. Thanks to otrsean at reddit for mentioning this option.
Another option could be to use your knowledge of music theory and identify the chord — like the G79 in the example above. Now you can rearrange the chord to better fit your hand, while still remaining a G79 chord. I would immediately get rid of the doubled third (B) in the left hand. You can then move up the bass note G an octave. This leaves you with G, B and F as a closed voicing in the left hand and G, D, A as a wide voicing in the right. If the right hand is still too much of a stretch for you, simply get rid of the doubled bass note (G) in the right hand. This all would let you end up with: (left hand) G,B,F and (right hand) D, A.
Let me know if one of these options worked for you! Also feel free to check out my YouTube channel for more tutorials.