KEYBOARD SHORTCUTS FOR PHOTOSHOP

You'd think setting up your content in Photoshop would be second nature; but oftentimes, the shortcuts to change the background size or zoom in to your project aren't what you think. 

Here are some of the most crucial shortcuts to know:

Selecting
Draw Marquee from Center	Alt-Marquee
Add to a Selection	Shift
Subtract from a Selection	Alt
Intersection with a Selection	Shift-Alt
Make Copy of Selection w/Move tool	Alt-Drag Selection
Make Copy of Selection when not in Move tool	Ctrl-Alt-Drag Selection
Move Selection (in 1-pixel Increments)	Arrow Keys
Move Selection (in 10-pixel Increments)	Shift-Arrow Keys
Select all Opaque Pixels on Layer	Ctrl-click on Layer Thumbnail (in Layers panel)
Restore Last Selection	Ctrl-Shift-D
Feather Selection	Shift-F6
Move Marquee while drawing selection	Hold Space while drawing marquee
Viewing
Fit on Screen	Double-click on Hand tool or Ctrl-0
100% View Level (Actual Pixels)	Double-Click on Zoom Tool or Ctrl-Alt-0
Zoom in	Ctrl-Space-Click or Ctrl-Plus(+)
Zoom out	Alt-Space-Click or Ctrl-Minus(–)
Hide all tools and panels	Tab
Hide all panels except Toolbox and Options bar	Shift-Tab
Rotate through full screen modes	F
Scroll image left or right in window	Ctrl-Shift-Page Up/Down
Jump/Zoom to part of Image	Ctrl-drag in Navigator panel
Toggles layer mask on/off as rubylith	\
Layer Shortcuts
Create new layer	Ctrl-Shift-N
Select non-contiguous layers	Ctrl-Click layers
Select contiguous layers	Click one layer, then Shift-Click another layer
Delete Layer	Delete key (while in the Move tool)
View contents of layer mask	Alt-Click layer mask icon
Temporarily turn off layer mask	Shift-Click layer mask icon
Clone layer as you move it	Alt-Drag
Find/Select layer containing object	Right-Click on the object w/Move tool
Change layer opacity	Number pad keys (w/Move tool selected)
Cycle down or up through blend modes	Shift-Plus(+) or Minus(–)
Change to a specific blend mode	(w/Move tool) Shift-Alt-letter (ie: N=Normal, M=Multiply. etc.)
Switch to layer below/above current layer	Alt-[ or Alt-]
Type Shortcuts
Select all text on layer	Double-Click on T thumbnail in Layers panel
Increase/Decrease size of selected text by 2 pts	Ctrl-Shift->/<
Increase/Decrease size of selected text by 10 pts	Ctrl-Shift-Alt->/<
Increase/Decrease kerning/tracking	Alt-Right/Left Arrow
Align text left/center/right	Ctrl-Shift-L/C/R
Painting
Fill selection with background color	Ctrl-Backspace
Fill selection with foreground color	Alt-Backspace
Fill selection with foreground color using Lock Transparent Pixels	Shift-Alt-Backspace
Fill selection with source state in History panel	Ctrl-Alt-Backspace
Display Fill dialog box	Shift-Backspace
Sample as background color	Alt-Click w/Eyedropper tool
To get Move tool	While in any painting/editing tool-hold Ctrl
To get Eyedropper with Paint tools	Alt
Change paint opacity (with Airbrush OFF)	Number keys
Change paint opacity (with Airbrush ON)	Shift-Number keys
Change Airbrush flow (with Airbrush ON)	Number keys
Change Airbrush flow (with Airbrush OFF)	Shift-Number keys
Cross-Hair Cursor	Any painting/editing tool-turn Caps Lock on
Decrease/Increase Brush Size	[ or ]
Decrease/Increase Hardness of Brush	Shift-[ or Shift-]
Switch between preset Brushes	< or >
Open Brushes pop-up panel	Right-Click in Image window
Erase to History panel's source state	Alt-Eraser
Cycle down or up through blend modes	Shift-Plus(+) or Minus(–)
Change to a specific blend mode	Shift-Alt-letter (ie: N=Normal, M=Multiply, etc.)
Create fixed color target from within a dialog box	Shift-Click in image window
Delete fixed color target	Alt-Click on target with Color Sampler tool
Create new spot-color channel from current selection	Ctrl-Click on New Channel button in Channels panel
Pen Tool Shortcuts
To get Direct Selection tool while using Pen	Ctrl
Switch between Add-Anchor and Delete-Anchor Point tools	Alt
Switch from Path Selection tool to Convert Point tool when pointer is over anchor point	Ctrl-Alt
To Select a whole path w/Direct Selection tool	Alt-click
Convert path to a selection	Ctrl-click on path name (in Paths panel)
Panel Shortcuts
Show/Hide Brushes panel	F5
Show/Hide Color panel	F6
Show/Hide Layers panel	F7
Show/Hide Info panel	F8
Show/Hide Actions panel	Alt-F9
Open Adobe Bridge	Ctrl-Alt-O
Other Shortcuts
Switch between open documents	Ctrl-Tab
Undo or Redo operations beyond last one	Ctrl-Alt-Z/Ctrl-Shift-Z
Apply Last Filter	Ctrl-F
Opens Last Filter Dialog Box	Ctrl-Alt-F
Hand Tool	Spacebar
Reset Dialog Box	Hold Alt, Cancel turns into Reset Button, Click it
Increase/Decrease value (in any option field) by 1 unit	Up/Down Arrow
Increase/Decrease value (in any option field) by 10 units	Shift-Up/Down Arrow
Replay last Transformation	Ctrl-Shift-T
Measure Angle between Lines (Protractor Function)	After ruler is drawn, Alt-Drag end of line with Ruler Tool
Move Crop Marquee while creating	Hold Space while drawing
Snap Guide to Ruler ticks	Hold Shift while dragging
Highlight Fields in Options bar (n/a for all tools)	Enter
Don't Snap object edge while moving	Hold Control while dragging

Tools
V	Move
M	Marquee tools
L	Lasso tools
W	Quick Selection, Magic Wand
C	Crop and Slice Tools
I	Eyedropper, Color Sampler, Ruler, Note, Count
J	Spot Healing Brush, Healing Brush, Patch, Red Eye
B	Brush, Pencil, Color Replacement, Mixer Brush
S	Clone Stamp, Pattern Stamp
Y	History Brush, Art History Brush
E	Eraser tools
G	Gradient, Paint Bucket
O	Dodge, Burn, Sponge
P	Pen tools
T	Type tools
A	Path Selection, Direct Selection
U	Rectangle, Rounded Rectangle, Ellipse, Polygon, Line, Custom Shape
K	3D Tools
N	3D Camera Tools
H	Hand
R	Rotate View
Z	Zoom
D	Default colors
X	Switch Foreground and Background colors
Q	Quick Mask Mode
To switch between all tools within groups, add the Shift key to the letters above
For example, to switch between rectangular and elliptical marquee hit Shift-M