The 2026 NFL Draft Combine Shapeshifters

Measure twice, cut once

Mar 02, 2026

Good evening everyone,

We’re coming off a huge weekend of NFL draft related content centered around last weekend’s combine. And something I pointed out last year dominated the news cycle: the art of numbers. Check out this tweet from Adam Schefter to see what I mean:

Although there are official measurements taken in Indianapolis, how correct are they? The news cycle was dominated by disputes over Carnell Tate’s 40 yard dash time and Reuben Bain’s arm length, but can we trust this data? Should we trust what the numbers tell us, what our eyes tell us, both, or neither? To throw a wrench in the numbers, we’re going to analyze the shapeshifters class of 2026. A shapeshifter is someone who magically changed their measurements between their officials at the Senior Bowl and the combine.

Preface

Those who were here last year can skip this part, but most of you all are new so I thought I’d include this part right here. This exercise began during the 2025 NFL Combine as a way to get familiar with principal component analysis (PCA). Check out last year’s write-up for more.

Here’s what last year’s vizzes looked like:

As you can see, I’ve learned a lot about layouts since then.

A lot can obviously change in 27 days, especially since prospective NFL players spend months just training for these combine drills. Some things are more in our control as humans than others. It’s relatively easy to cause big swings in your weight in almost 4 weeks. But what about arm length? Hand size? Why do those change so much in that timeframe? I think this will resonate with anyone who’s ever bought a pair of shoes that are supposed to be their size but they end up being too narrow or roomy in the toe box. There’s art to this science. There’s nuance and human error surrounding all of these ‘official’ measurements.

The Data

I’ve been working independently on a combined, coalesced NFL combine dataset since 2022. It has multiple sources, like NFLCombineResults.com, nflreadR, Daniel Jeremiah’s rapid measurement tweets, and straight from the horse’s mouth, NFL.com. I’ve uploaded it as CSV and Parquet files on GitHub if you want to take a look. These serve as the backbone of my NFL Draft Comparison Card visualizations that attempt to combine production stats and measurables to create percentile groupings for draft comps. The Combine’s broadcast added these comps too, and here’s one Daniel Jeremiah pointed out:

And here’s one I made with just the data:

Pretty cool, if I say so myself. You can create these comparison cards yourself for every prospect since 2007 here.

nflreadR’s combine dataset goes back to 1987, but mine only goes back to 2007. I considered folding that in, and probably will backfill it on a future date. But for the sake of speed and filtering, I didn’t want to add a bunch of combine data I didn’t have matching college stats for. There are already some underlying integrity issues, like how no one has numbers for how many fumbles DeMarco Murray had in college. I point these things out for the sake of transparency. Oftentimes I see data visualizations online and I have two questions that are never answered, that I have to answer constantly at work. Where did you get the data? How do you know it’s correct? Familiarizing myself with the source data similarly to how someone would a book they’re reading is the only way.

I had a lot of great feedback and help on this dataset from my Twitter followers.

107 players measured in at the Senior Bowl and Combine, let’s compare them.

Weight Shapeshifters

Let’s start with one actually in the prospect’s control, and not too farfetched, weight differences:

We’ve got 94 out of 107 players bulking or cutting over the last month. 94 players gained or shed weight. Maryland OT Alan Herron is tied with Illinois OT JC Davis as the biggest loser with 13 pounds lost, and UCF DE Nyjalik Kelly gained 17 pounds in a month. He must’ve been drinking tons of Ben Bartch smoothies.

This one is the least extreme outcome, because we see this all the time with UFC fighters, wrestlers, and boxers. Of course prospective NFL players are going to apply these methods to their first official NFL weigh-in. Let’s move on to a more ridiculous shapeshifting effort. Weight fluctuates throughout the day. That many 1 pound swings could be the result of heavier or lighter clothing, or ounces of water.

Arm Length Shapeshifters

As we all know, an arm’s length is the be-all, end-all when it comes to measurement estimates. Arm length has dominated public narrative since last season when Will Campbell fell victim to T-Rex related online vitriol. Then football fans used this against him again when he messed up a few snaps against the unanimous best defense in the league in the Super Bowl. Similar sentiment applied to Reuben Bain Jr. last weekend, prompting a more than likely agent-ventriloquist style tweet from Adam Schefter. So because the general public is so laser-focused on a player’s arm length, surely it’s a deadly accurate measure, right?

Oh. 96/107 players showed discrepancies between Combine arm length and Senior Bowl arm length. No one had longer arms a month ago than they did last weekend, but 96 people had shorter arms. This raises some more questions regarding the definition of an arm, and the definition of an inch. If anyone has any leads on workouts to target increasing arm length, please let me know.

Side note: Edited this after posting it to Twitter saying ‘top 20’ instead of ‘top 25’. I’m a fan of typos now though. It helps convey to my readers that I’m making these charts by hand.

Hand Size Shapeshifters

Now onto another metric you can’t really change with working out, hand size:

Seeing multiple prospects with a ⅜ inch difference between their Senior Bowl hands and their Combine hands. This one might be explainable though. My first hypothesis was to look at weather data comparing the Senior Bowl’s location of Mobile, AL to the Combine’s location of Indianapolis, IN. But Mobile was experiencing a weird cold spell of weather during the Senior Bowl, so both average daily temperatures remained in the 50s in both places for both events. Could it have something to do with humidity? Or maybe blood flow to the hands that can increase hand size temporarily? All interesting questions worth investigating on another day.

Height Shapeshifters

100 differences in height between the Senior Bowl and Combine. 15 players were a half an inch taller.

What if we scale?

If we calculate the z-scores of each measurement (standard deviations away from the set’s mean), we can rank players based on how much they’ve changed between the Senior Bowl and Combine:

Maryland OT Alan Herron is our winner this year. And if we look at the measurements themselves, we can use percent difference to try and crown the shiftiest measurement. The winner is hand size, changing by 2.28% on average between the Senior Bowl and Combine. Second place was weight, by 1.76%, arm length by 1.24%, and height by .4%. My underlying assumption was that it would be arm length, based on all the discourse. Or weight, based on human experience. How could hand size fluctuate more than weight?

The Point I’m Trying to Make: We Should All Calm Down

Let’s return to those two questions I presented you with in the intro.

Where did you get the data?

I pulled Senior Bowl Data from A to Z sports on February 10, 2026. I pulled it again on March 2, 2026 to make sure nothing changed in that time frame.
I pulled combine data from NFL.com and upserted my combine dataset with the data (inserted new records, updated existing ones).

How do you know it’s correct?

The combine data is directly from NFL.com, so if they’re wrong then I’m wrong.
The Senior Bowl data however is much harder to get actual measurements for. Some quick Googling yields a couple of websites claiming to be the ‘official’ source, I just went with A to Z Sports because it was easiest to parse.

So how many pairs of hands has this data been in? It’s a gigantic version of data whisper down the lane. I love the combine so much because it really shows the art of data, and how measurement variance can change up an entire narrative. That’s why I posted comparison model cards as new measurements folded in. Remember that Jeremiyah Love card? This was the card I generated for him pre-40 yard dash time:

The Twitter universe wasn’t happy about this one, which indicates two trends to me. First, no one has any idea how good Chuba Hubbard was in college. And second, everyone takes too much stock in measurements. The Combine is just one dimension of an entire life’s work. To disparage a player’s abilities just because of one eighth of an inch of arm length (which may or may not be accurate to begin with) is simply unfair.

Go and watch these guys play football. I promise you’ll love what you see.

Football’s a game of inches. It’s not a game of eighths of inches.

Beeswarm Drill Plots

For the dataset ranging from 2007 to 2026, here’s the spread of Combine drill results by position group. I have two beeswarm plots for each drill, one with just Combine stats and one with Combine stats coalesced with pro day stats. That just means if a player didn’t run a 40 yard dash at the Combine but did run one at his pro day, we filled in the pro day 40 time. Here are the results:

First, the bench press spread: