Couple of sells before the words to ring the till’s bells. If you want an ad-free experience, click here. Join a Razzball League, they’re filling up, but they need youse, so stop being afraid of success! Finally, Rudy released his War Room, you need to subscribe to our tools to get it. Not to toot Rudy’s horn — ew! — but it is what we both use in all our drafts. I’m basically crediting it with our Tout Wars wins. It is leaps and bounds better than our online War Room. It is indispensable in NFBC leagues. You can get access to the War Room via the Easter Egg hidden in the middle of the Stream-o-Nator page. You have to subscribe, though. Speaking of NFBC, sign up to take on Rudy or Ralph or MattTruss or yours truly. League’s start drafting March 4th. Wait, there’s a more detailed intro:
Time to sign up for those of you interested in competing against some Razzball writers (including Grey who won his league two years in a row; man, can’t anyone beat him? He’s better at NFBC than he is at not talking in third person!) in the NFBC $150 Draft Champions format. It is a 15 team mixed, 5×5 format with 50 rounds (done via a slow draft that takes about 2 weeks). NFBC’s moved to a new site that looks great and they have cut the clock between picks from 8 hours to 4 hours (except overnight).
For those unfamiliar, the major quirk vs most league formats is that there are no trades OR free agent pickups. You can update your starting hitters twice a week (Friday and Monday) and pitchers once a week (Monday). I love this format as a complement to standard formats as it rewards drafters who can find breakout candidates/bargains on draft day.
Once we have enough people to fill a league, NFBC will create the league. I recommend creating an account at NFBC if you do not have one as that will expedite everything. Put your email in the signup form below to play against us.
NOTE: THIS IS SEPARATE FROM THE RAZZBALL COMMENTER LEAGUE. THAT IS A 12-TEAM MIXED FORMAT WITH DAILY ROSTER CHANGES AND YOU CAN PLAY IN FREE, $10, OR $20 LEAGUES. SIGN UP HERE IF YOU ARE INTERESTED.
Any hoo! (Holy Hayzeus that was an intro), when I searched for K/9 vs. K%, the first page of Google had links dedicated to buying drug-sniffing dogs headed for retirement. Forced retirement of drug-sniffing dogs is a serious problem, and they have no leaders to unionize them. Complex issue that we don’t have space to delve into here. By the way, it would be a hilarious prank to buy your biggest pot-smoking friend a retired drug-sniffing dog. “Dude, this dog you bought me barks at my coffee table bong all day and it’s freaking me out.” My point is, K/9 vs. K% hasn’t been well-explored. One article I found on Fangraphs was written in 2014. This is evergreen information, as they say in the biz (weed biz and otherwise), so there’s no reason to think the post is outdated simply because it’s 2014. They wrote how the clearcut winner for the best stat was K%. Expanded on why. Their reasoning was sound. Their conclusion, however, was:
Then I cackled for about five hours. In case you’ve been living in a cave for the last few years, and not a mancave, Tyler Chatwood’s been a bit better than Lincecum, but, then again, you’d be hard-pressed to find someone who has been as bad as Lincecum. Just a few months after this article was written the wheels completely came off of Lincecum. Hmm, maybe there’s more to drug-sniffing dogs relating to K/9 and that’s why Lincecum tanked? Any hoo! This isn’t about Chatwood or Lincecum, it’s about K/9 vs. K%. Finally, onto the battle:
What are the differences between K/9 and K%?
Why does this feel like I’m writing a tutorial on eHow? This is such a post you’d find on the internet in the mid-2000’s when they still capitalized the word internet. “What are the differences between ‘early birds’ and ‘morning larks?’ A brief discussion.” Okay, so outdated mode of translation aside, what K/9 is is (stutterer!) obvious. The formula is in the name. How many batters a pitcher strikeouts per nine innings. K% is strikeouts/total batters faced. They are, sadly, not the same thing. If they were the same thing, this would’ve been such a shorter article! Keeping with the mid-2000’s style I’ve adopted for this article, let’s do a subheading in bold!
Examples of how K/9 and K% differ:
A pitcher, let’s call him Gon Jray, enters the 1st inning charged up about how great he’s going to be against these good-for-nothing Dan Siego Madres. Gon gets the first Madre to pop-up. What a start to the 1st inning! Then Gon strikes out the next hitter. Wow, this Gon guy is a-okay! Then the next 15 Madres get on and score 10 runs. Finally, he gets another grounder to the left side to end the inning. Not the best start, since he threw 135 pitches in one inning and has a 90.00 ERA, but Gon’s hoping to get ’em next time!
Another pitcher, let’s call him Schax Merzer. He gets to face those same Dan Siego Madres! What a treat and great for comparison’s sake. Merzer gets the first two Madres to ground out and he Ks the third hitter. That sounds a bit better than Gon Jray’s start, but:
They both have a 9 K/9.
That’s the problem with K/9. A pitcher who throws a perfect game with 9 Ks and a pitcher who throws 5 IP, 5 ER with 5 Ks, both have a 9 K/9.
However, their K% differ. Gon Jray’s K% is 11, whereas Merzer’s K% is 30. If it’s not clear 11% is insanely terrible. Last year’s worst K% was Mike Leake at 15.2%, and Chris Sale was best at 38.4%. Common knowledge should tell you if you’re striking out a guy nearly 30% of the time, it’s excellent. Mean’s while, if you strike out a guy nearly 15% of the time, it’s not good. Face 27 batters and that’s 4-ish Ks for 15% of the time; 30% is 8-ish Ks. Simply math, guys and five girl readers, let’s continue!
K% is more accurate than K/9.
Oops, just put it out there like I don’t have a care in the world. Just chucking out truisms and not even with a warning!
So, why is it I use K/9 more often than K% when discussing pitchers for fantasy baseball?
This, I think, is a more of a philosophical question. K/9 is talking plainly, while K% is less obvious. If you hear a 9 K/9, it equates in your head immediately that a guy strikes out nine batters in nine innings. It’s super clean. K% is talking about batters faced, and that changes each inning. A 30% strikeout rate is great, but that’s not obvious on its face. While K/9 is not perfect, it is easier. Plus, K/9 and K% usually line up fairly closely for starters. If a guy has a 38.4 K%, he’s going to have a great K/9.
K/9 does give some false hope. Pitchers you should be wary of no matter what their K/9 is telling us:
| Pitcher | K/9 | K% |
| Robbie Ray | 12.01 | 31.4 |
| Zack Godley | 9.34 | 23.4 |
| Lance Lynn | 9.25 | 23 |
| Sonny Gray | 8.49 | 21.1 |
| Danny Duffy | 8.19 | 20.4 |
Robbie Ray has the 5th best K/9, but the 8th best K%. Bit of a quibble, p to the erhaps, but his K/9 is covering a wildly awful walk rate. To a lesser extent, same for Zack Godley, Lance Lynn, Sonny Gray and Danny Duffy. Of course, no one should look at just one stat for anything. Does a pitcher have two pitches or four? Does he get killed by lefties or righties? Does he allow a ton of walks? You need to look at the whole picture, ahem, pitcher.
K% matters more for relievers.
With fewer innings a reliever can throw, these things become more pronounced. Matt Barnes, for unstints, had a 14.01 K/9, but a 36.2 K%, because he’s walking the house and his batting average against was not nearly as elite as other relievers around him in strikeout rate. Barnes’s BAA was .203, but Jose Leclerc had a 13.27 K/9, but a .123 BAA and a 38.1 K%. Now, if I told you Barnes’s 14.01 K/9 was not as good as Leclerc’s 13.27 K/9, you may have been confused, but if you literally just read the sentence before this, you’d understand why. Barnes also had a higher BABIP, and maybe he was unlucky, that’s why you then need to look at line drives, how hard balls were hit off him, where they were hit, and…Do you see the rabbit hole you can go down? This is also why you have to pick and choose poisons and which stats to use.
So, what is best for fantasy baseball — K/9 or K%?
I prefer K-BB%. Whoa, 3rd act plot twist! K-BB% doesn’t say everything — nothing does. It says quickly that a guy strikes out more guys than he walks, and that’s usually a good thing. If a guy does K-BB% well, then, well, unless you’re Masahiro Tanaka, you’re usually okay. (You need to look at homers allowed too, in that example. See, nothing is perfect on its own.)
