The Green Reading System from WhyGolf is a must have addition to you green reading tool box. I have recently added this system to my training aid arsenal. Let’s take a look.
Just to be up front, I’ve shied away from WhyGolf products for some time. Most of the stuff they make I already have in some other form and made by a different company.
So why would I recommend this green reading system?
It has a couple components no one else offers.

Green Reading System – From WhyGolf
Ever get paired with a caddie who can tell you the break of every putt? It’s a pretty empowering experience.
But what’s even more empowering is when you can do it yourself.
Our Green Reading System was created to teach every golfer how to become a Tour-caliber green reader. According to science, our feet are better at feeling slope than our eyes are at seeing it. The Slope Plate trains your feet to read subtle changes in slope. From there, our Green Cards will show you EXACTLY how much your putt is going to break and where you should aim.
Included with Purchase:
- Slope Plate (Feel the Break)
- Green Cards (Know Where to Aim)
- Custom Training Videos w/ In-Depth Instruction
- 99 Day Money-Back Guarantee – Not happy? Send it back for a full refund.

My description of what this is
The kit includes a slope plate which is an indoor green reading aid that you stand on to practice reading greens.
I like the slope plate. It sits on a “level” floor and I just go over and step on it.
The idea being that you guess the amount of slope you are standing on in percent of slope.
You simply look down and which ever number is in the middle of your feet is the correct read.
You can make up your own game, drill or rules. I usually make 10 attempts and keep score. In other words, was I right or wrong and how many times was I right.
The slope plate has a built in space for a bubble level and 2 are provided in the kit.
The part of the system that I had from another company was the green reading cards.
These are different. By that I mean these actually give you the read.
The cards are for 8, 9, 10, 11, 12, and 13 stimp greens.
You get the green read for flat, uphill or downhill putts with break up to 4%.
It also includes a small stimp meter. I’m very surprised that it actually works. My plan is to put it into my golf bag to lighten my load.
Why 4% max on the Green Cards
The generally recommended slope for pin placement in golf is a maximum of 3% on greens running at or above 10 stimp. This means that the pin should ideally be placed in an area where the slope around the cup is no more than 3%.
Elaboration:
- 3% is a common guideline: Many sources recommend a 3% maximum slope for pin placement.
- Greens running at 10+ stimp: This guideline is particularly relevant for greens that are running at 10 stimp or higher, which is common for championship courses and faster greens.
- Why the 3% limit? Steeper slopes make it harder for golfers to control their putts, as the ball may roll away from the hole or even roll back toward the golfer.
- USGA recommendations: The USGA, while not having specific rules about pin placement on slopes, does recommend that holes be placed in areas where there is a relatively level area of at least 3 feet around the hole.
Here is an article on the definition of “Full Planar.” In other words, where should a pin be located.
Conclusion
What do I like? The Slope Plate and Stimp Meter.
The Green Cards…not so much.
I haven’t seen another slope plate anywhere. WhyGolf makes good products. This is very well made.
The stimp meter actually works well even though it’s only a foot long. It’s going in my golf bag.
You do need to roll the ball on a level area of the green on a line in both directions like any stimpmeter to double check the roll distance.
My PuttOUT Air Break is rated at 10 stimp. The WhyGolf stimp meter read that right on the money.
My opinion of the cards is that they are one more thing to mess with. In addition, they only go up to 4% slope and out to 10 paces.
They are OK, but there are better ways to read greens without cards.
I measured the greens on my local course. The one I usually play on. It has places where they put the pin that are greater than 4% slope.
There are places on all the courses I play on where you can putt right off the green.
I’ve measured much more than 3% or 4% slope on greens. Even where the pin was located.
I think the cards might be good for some people….not for me.
Here is a link to a more reasonable method that can be used to determine break and aim line.
You need to be able to feel slope with your feet. No matter how steep the slope is.
Your eyes can let you down.
That is why I like this system. At least I can practice and recognize up to 4% slope in the house.
I can take that to the course and build on that where needed.