Every Sunny fan has the same theory. Peak Sunny was the FX run. Anything past Season 10 is the gang on autopilot. They should have ended it at 'The Gang Goes to Hell.'
We just scored every joke in every episode of It's Always Sunny in Philadelphia — 8,786 jokes across 177 episodes, three independent AI passes each — and the data tells a different story. The last five seasons are not a decline. They're the peak.
The headline
On the Humor Index, the full series averages 79.2. The "Renaissance arc" cut — Seasons 13 through 17 — averages 80.4, +1.2 above the full-series number. The "Cult era" cut — Seasons 1 through 7, the FX heyday — averages 77.3, –1.9 below. That's a three-point gap between the two halves of the same show. Same five leads. Same writers' room core. Different decade.
Built the cut yourself: Sunny Renaissance arc (S13–S17) →
Season by season
Here's the per-season scoring across all 17 seasons (display HI, with our 95% bootstrap CI on each):
| Season | HI | Episodes | Era |
|---|---|---|---|
| S15 | 82.8 | 8 | Renaissance |
| S17 | 81.2 | 8 | Renaissance |
| S09 | 80.8 | 10 | Transition |
| S14 | 80.0 | 10 | Renaissance |
| S13 | 79.6 | 10 | Renaissance |
| S11 | 79.5 | 10 | Late |
| S12 | 79.1 | 10 | Late |
| S08 | 79.0 | 10 | Transition |
| S16 | 78.5 | 8 | Renaissance |
| S07 | 78.0 | 13 | Cult |
| S10 | 78.0 | 10 | Transition |
| S01 | 77.9 | 7 | Cult |
| S03 | 77.6 | 15 | Cult |
| S04 | 77.4 | 13 | Cult |
| S05 | 77.2 | 12 | Cult |
| S06 | 76.5 | 13 | Cult |
| S02 | 76.4 | 10 | Cult |
Seven of the top nine seasons are post-S10. No Renaissance-era season drops below 78.5; no Cult-era season climbs above 78.0. Three of the five Renaissance seasons reach 80 or better; and no Cult season comes closer than two points to it. The cleanest split on the entire show falls right around the mid-2010s. Whatever happened to Sunny in 2015 happened for the better, by the numbers.
So what's actually changed?
The gang got meaner.
This isn't us editorializing — it's what the per-joke scores show. The single biggest gap between early and late Sunny isn't joke density — the two eras tell jokes at effectively the same rate (1.70 per minute in the Renaissance era vs 1.77 in the cult era — a difference well inside run-to-run noise). It isn't run-time. It's impact and dark/subversive weight. Same joke rate, three more points of Humor Index.
Late-season Sunny leans hard into joke types our model rates higher per beat: dark/subversive, character comedy from sustained malice, cringe escalation, callbacks that take a full season to detonate. Early Sunny had to introduce itself — establishing the gang's awfulness in every episode, often with broader, more setup-heavy joke construction. Late Sunny doesn't have to introduce anything. The audience knows. The gang gets to lean directly into the punch.
The single best episode is a Renaissance episode
The #1-ranked Sunny episode of all 177, by Humor Index, is "The Gang Goes to Hell (1)" — S11E09, HI 92.8. Number two is "The Gang Gets Cursed" — S16E03, HI 91.5. Number three is "The Gang Gets Analyzed" — S08E05, HI 91.1 (the closest a pre-S11 episode comes to the top of the list).
Of the top 15 episodes by Humor Index, eight are S11 or later. Six come from the pre-S10 era and one from S10 — closer than the season averages suggest, because the cult era's ceiling was always high; it was the floor that moved. The fan-favorite Cult-era classics — Dennis Looks Like a Registered Sex Offender, The Nightman Cometh — are great episodes. They're just not, on average, the show's best work. (The Gang Gets Analyzed is the exception that proves it: at 91.1 it is the third-best episode in the series, and it is from Season 8, after the cult era had already ended.) The show's best work happened after most casual viewers stopped paying attention.
Where the data could be wrong
We're trying to keep the honesty receipts updated on this site, so:
- Single-run scorer noise is real. Our intraclass correlation between AI passes on the same episode is around 0.28 on individual runs — meaning ~72% of episode-level variance is scorer noise. We pull that down hard with the 3-run consensus we use here, but it's worth flagging.
- Cluster overlap. The 95% bootstrap CI on the Renaissance cut is 78.8–81.9. The CI on the Cult cut is 76.1–78.4. They don't overlap, but only just — and they're a lot closer than the three-point gap suggests at a glance.
- Late-season Sunny rewards rewatch. A lot of Renaissance joke craft is callbacks ("The Implication" turning up six seasons later, "Wild Card, Bitches!" landing as a payoff). Our scoring credits callback craft. If you've never seen early Sunny, half of S15 is just nonsense.
The picture isn't that "Renaissance Sunny is funnier" in some absolute sense — it's that the writing got tighter, the jokes earn more, and the gang's sustained awfulness has had two decades to compound. Whatever your fan theory of when Sunny peaked, the data has a different one. Build your own cut →
Scale note: 13 of our 21 shows have been rescored on the current canonical model. Eight — The Office, Friends, Curb Your Enthusiasm, It's Always Sunny, Community, Futurama, Taxi and The Fresh Prince of Bel-Air — are still on the pre-2026 scale and will move when they're rescored. Comparisons that mix the two are flagged where they appear.