There is no formula for drafting a quarterback.

This will be on display again on April 26 when as many as six quarterbacks are projected to go in the first round and four might go in the top 10.

This college quarterback class has been heralded as one of the best in years. Yet, there is no consensus on who is the best quarterback in this class, and there is no predicting how any of these quarterbacks will fare as professionals.

With the Giants and Jets possibly primed to select quarterbacks next week, The Post examined some of the characteristics of the top 15 current NFL quarterbacks (based on average QBR over past three seasons) displayed coming out of college to see if anything could be gleaned from it and how the top four quarterbacks in this year’s draft compare. Here is what we found:

Based on average QBR from past three seasons (In alphabetical order)

Tom Brady, Patriots
Drew Brees, Saints
Kirk Cousins, Vikings
Andrew Luck, Colts
Carson Palmer, retired (Cards) this year
Dak Prescott, Cowboys
Philip Rivers, Chargers
Aaron Rodgers, Packers
Ben Roethlisberger, Steelers
Matt Ryan, Falcons
Alex Smith, Redskins
Matthew Stafford, Lions
Tyrod Taylor, Browns
Carson Wentz, Eagles
Russell Wilson, Seahawks

Tallest

Carson Palmer           6-5
Philip Rivers              6-5
Ben Roethlisberger   6-5
Carson Wentz            6-5
Tom Brady                 6-4
Andrew Luck             6-4
Matt Ryan                  6-4
Alex Smith                 6-4

Shortest

Dak Prescott             6-2
Aaron Rodgers         6-2
Tyrod Taylor            6-1
Drew Brees              6-0
Russell Wilson          5-11

Prospects
Josh Allen                6-5
Sam Darnold           6-4
Josh Rosen              6-4
Baker Mayfield       6-0

Analysis: Most of the top QBs are big. It helps them see clearly over the line and down the field. Big QBs are also tougher to take down, as Roethlisberger has shown over the past 14 seasons. However, Russell Wilson and Drew Brees have shown that smaller quarterbacks can succeed.

In this year’s group, Mayfield measures a shade under 6-foot-1, which is one of the biggest concerns team have about him. On the other side, scouts love Allen’s size. He has drawn comparisons to Roethlisberger and Wentz because of his large frame.

Biggest

Dak Prescott           10 7/8
Drew Brees              10 ¼
Russell Wilson        10 ¼
Andrew Luck           10
Matthew Stafford   10
Tyrod Taylor           10
Carson Wentz         10

Smallest

Carson Palmer        9 ½
Matt Ryan                9 ¹/₂
Aaron Rodgers        9 3/8
Alex Smith               9 3/8
Philip Rivers           9 ¼

Prospects

Josh Allen                10 1/8
Josh Rosen                9 7/8
Sam Darnold             9 3/8
Baker Mayfield         9 ¼

Analysis: Hand size has become a key measurement for QBs in the draft in recent years. Teams believe big hands means better ball security, particularly in cold weather. A few years ago, Jared Goff’s 9-inch hands drew a lot of questions. Brady’s hand size is unknown. It was not measured at the combine when he was in the draft.

The interesting thing in looking at the current NFL players is that two of the smaller players in the league have big hands. Brees and Wilson are both pointed to as examples of shorter quarterbacks having success. Both have 10 ¼-inch hands.

Coincidence?

Mayfield has been compared to those two because of his height, but his hands are just 9 ¼ inches. Should that scare off cold-weather teams?

High Scores

Alex Smith              40
Carson Wentz         40
Matthew Stafford   38
Andrew Luck           37
Aaron Rodgers        35

Low Scores

Drew Brees               28
Russell Wilson         28
Carson Palmer          26
Dak Prescott              25
Ben Roethlisberger  25
Tyrod Taylor              15

Prospects

Josh Allen                37
Josh Rosen              29
Sam Darnold           28
Baker Mayfield        25

Analysis: The Wonderlic is an intelligence test first used in the NFL by Hall of Fame Cowboys coach Tom Landry. There is debate as to how much teams can learn from it but it is still used by the NFL, and QBs are expected to do well on it. Two former Jets both scored 48 on the Wonderlic, the highest known score for a quarterback — Ryan Fitzpatrick and Greg McElroy.

This year’s top four all did fairly well on the Wonderlic, and there should not be any concerns from teams about their scores. Allen’s score stands out and may impress someone.

Big Ten         4
Pac 12          3
ACC              3
SEC              2
MAC              1
Mount. W.     1
Miss Val.        1

Prospects
Pac 12           2
Big 12            1
Mount. W.     1

Analysis: The big conferences dominate here, as you would expect. The exceptions are Roethlisberger (MAC), Smith (Mountain West) and Wentz (Missouri Valley). Wilson could actually count for both the Big Ten and the ACC, since he went to N.C. State before playing a year at Wisconsin.

The question with this year’s group is can a Big 12 quarterback be successful in the NFL. Mayfield comes from the wide open Oklahoma offense played by many in that conference. It has not translated into NFL success, though it should be noted the Chiefs are banking on Patrick Mahomes II out of Texas Tech to be their franchise quarterback. There is also concern that Allen did not dominate the Mountain West last year.

Highest

Andrew Luck             67.0
Alex Smith                 66.3
Ben Roethlisberger  65.5
Kirk Cousins              64.1
Carson Wentz            64.1

Lowest

Russell Wilson         60.9
Matt Ryan                 59.9
Carson Palmer         59.1
Tyrod Taylor              57.2
Matthew Stafford      57.1

Prospects

Baker Mayfield         68.5
Sam Darnold            64.9
Josh Rosen               60.9
Josh Allen                 56.3

Analysis: The 60 percent mark is the dividing line here. Anything under is seen as troubling by NFL teams. Stafford is proof that you can be a successful quarterback even with a low college completion percentage.

Allen’s completion percentage has been a hot topic for months. Is it a red flag or a product of him not having a strong supporting cast? Mayfield was the most accurate quarterback in college football last year. That also comes with questions, though. Was it because of the offensive system he played in?

Most

Philip Rivers      51
Russell Wilson  47
Carson Palmer  45
Tyrod Taylor     42
Kirk Cousins     40

Fewest

Matt Ryan          33
Tom Brady         25
Carson Wentz   23
Alex Smith         22
Aaron Rodgers  21

Prospects

Baker Mayfield   46
Josh Rosen         30
Josh Allen           26
Sam Darnold      24

Analysis: Bill Parcells used to say he did not like QBs who had not started a lot of games in college. Mark Sanchez came under scrutiny when he was drafted after starting just 16 games. Mitchell Trubisky also drew questions last year for starting just 13 games.

Once you get to the 20-start mark, this becomes less of a question. That means you have started for the better part of two years. None of the quarterbacks at the top of this year’s draft have experience questions.

Highest

Alex Smith            .955 (21-1)
Carson Wentz      .870 (20-3)
Aaron Rodgers    .810 (17-4)
Tyrod Taylor        .809 (34-8)
Tom Brady           .800 (20-5)

Lowest

Dak Prescott        .694 (25-11)
Philip Rivers        .667 (34-17)
Drew Brees           .649 (24-13)
Russell Wilson     .617 (29-18)
Carson Palmer     .600 (27-18)

Prospects

Sam Darnold         .833 (20-4)
Baker Mayfield     .826 (28-8)
Josh Allen             .615 (16-10)
Josh Rosen           .567 (17-13)

Analysis: This is usually more popular with fans than teams, but sometimes the argument is made that a quarterback is “a winner.” This was a popular argument from Tim Tebow fans.

Does college winning percentage matter? It definitely can indicate a QB is playing at a high level, but there are so many other factors that go into team success. Alabama’s quarterbacks would be top prospects every year if winning truly was an indication of a good quarterback.

Darnold and Mayfield own at a high clip. Teams have to figure out what value that has. Allen’s win percentage is a little low for playing in a weak conference. Look at what Wentz did against low-level competition. He dominated. Allen did not. That could hurt him.

Most

Carson Palmer         49
Drew Brees               45
Matt Ryan                 37
Philip Rivers             34
Ben Roethlisberger  34

Fewest

Tyrod Taylor            20
Tom Brady               17
Carson Wentz          14
Aaron Rodgers        13
Alex Smith                8

Prospects

Baker Mayfield       30
Josh Rosen              26
Sam Darnold           22
Josh Allen                21

Analysis: Do QBs who turn it over in college continue to turn it over in the pros? Generally, yes. Palmer and Brees both had seasons where they led the NFL in interceptions. Smith and Rodgers are known as two of the least turnover-prone quarterbacks.

Mayfield’s and Rosen’s totals are inflated because of how many starts they made. Darnold’s turnovers concern teams. They are studying his interceptions and trying to figure out whether the problem is a simple fix or something that will stay with him throughout his career.