Greenland paddle fit is usually determined by anthropometric (body) measurements. For a full-size paddle, a very common measurement is one arm span plus a cubit. A cubit is the distance from your elbow to your fingertips.
Otherwise, stand with the paddle close beside you, vertically. Reach up to the tip and just curl your fingers over the top of the paddle.
In windy areas and for ease in maneuvering the paddle underwater, some people prefer a slightly shorter paddle - an arm span plus the distance from the wrist to the fingertips.
"Storm" paddles (shorter paddles used with a full sliding stroke) are not as long as a regular size Greenland paddle. Storm paddles are typically one arm span long, with the loom only one, two or three fists wide.
Your kayak and your body determines loom dimensions. A good starting point is to stand, shake out your arms and allow them to hang at your sides. From this position bend your arms at the elbows so that your forearms are parallel to each other and horizontal to the ground.
Your elbows should not be held to your sides. Let them “float”. Now make a circle with the thumb and forefinger of each hand. These circles indicate where the paddle shoulders should be.
Generally, the loom must be at least as wide as your kayak. If your kayak is wider than a standard Greenland kayak, you may have to improvise.
Another method to determine loom length with respect to your kayak is to hold a broom handle while sitting in your kayak. Your hands will naturally fall in the right position, revealing the best spot for the shoulders of your paddle.
Blades can be as narrow as just over two inches to as wide as you can grip.
For your first paddle, choose a width somewhere these extremes that feels comfortable for your grip.
Paddle Sizing and Fit sourced from The American Chapter of the Greenland Kayaking Association, QAJAQ USA