Week 3 · Sun, 4:05 PM EDT · FOX
Arizona Cardinals at San Francisco 49ers
Levi's Stadium, Santa Clara, CA
Market line for comparison: SF -8.5 · O/U 47.5 (DraftKings). The model never sees this.
Rating inputs
Each starting rating is a weighted blend of five real football inputs, not just wins and losses. Every term below is measured from the 2025 season.
Arizona Cardinals
| Input | Rating | Weight | Contribution |
|---|---|---|---|
Elo from results 3-14 in 2025, opponent-adjusted | 1371 | 80% | 1096.8 |
Scoring strength 355–488 points (-133.0 differential) → 32.0% expected win rate | 1369 | 5% | 68.4 |
Late-season form same replay with the closing 6 weeks counted double | 1308 | 15% | 196.1 |
Offense / defense split 20.9 PPG scored, 28.7 allowed → offense 1447, defense 1358 | 1304 | 0% | 0.0 |
| Blended 2025 rating | 1361.4 | ||
Offseason regression 25% back toward the 1500 league mean | 1396.0 | ||
Roster / QB adjustment No offseason adjustment applied. | 0.0 | ||
| ARI 2026 starting rating | 1396 | ||
San Francisco 49ers
| Input | Rating | Weight | Contribution |
|---|---|---|---|
Elo from results 12-5 in 2025, opponent-adjusted | 1565 | 80% | 1251.9 |
Scoring strength 437–371 points (+66.0 differential) → 59.6% expected win rate | 1567 | 5% | 78.4 |
Late-season form same replay with the closing 6 weeks counted double | 1585 | 15% | 237.8 |
Offense / defense split 25.7 PPG scored, 21.8 allowed → offense 1567, defense 1530 | 1597 | 0% | 0.0 |
| Blended 2025 rating | 1568.0 | ||
Offseason regression 25% back toward the 1500 league mean | 1551.0 | ||
Roster / QB adjustment No offseason adjustment applied. | 0.0 | ||
| SF 2026 starting rating | 1551 | ||
The calculation
Every term the model applies, in order, from both teams' starting ratings to the number on the card.
Win probability
1 / (1 + 10−(107.2 / 400))
65.0% SF
Model spread
107.2 ÷ 25, rounded to the nearest half point
SF -4.5
Confidence band
Injury adjustment
Report pulled 2026-10-27 13:20 UTCRatings describe a team over a whole season. Who is actually available on Sunday is a separate question, so the injury adjustment is applied last, after home field and rest. Each listed player costs a share of a point of spread based on his position, whether he starts, and how likely he is to play.
Before injuries
74.3%
SF by 7.5
Injury term
−77.5 Elo
−3.1 pts of spread, home perspective
After injuries
65.0%
SF by 4.5 · moved 9.4 pts of probability
Arizona Cardinals
−0.9 pts
- Carson Beck QBOut−0.10
- James Conner RBOut−0.10
- Jeremiyah Love RBOut−0.10
- Jalen Brooks WROut−0.10
San Francisco 49ers
−0.8 pts
- Nick Bosa DEOut−0.10
- Demarcus Robinson WROut−0.10
- De'Zhaun Stribling WROut−0.10
- Deebo Samuel Sr. WROut−0.10
Statuses come straight from the league injury report: out and injured reserve count in full, doubtful three quarters, questionable roughly a third, probable a tenth. Starters are identified from the depth chart; anyone the model cannot place is treated as a backup.
Move the factors yourself
Every term feeds one number: the adjusted Elo difference. Drag any of them and watch the spread and confidence follow.
Drag to see how much a stronger or weaker host changes the call.
The two ratings only matter through their difference.
The tuned value is a flat 25 points for every host.
5 Elo per extra day of rest, capped at 25 either way.
A manual thumb on the scale, in the home team's direction.
Win probability
74.3% SF
Model value
Model spread
SF -7.5
Elo diff +184.7 · Confident
Probability curve
The logistic curve from −600 to +600 Elo, home perspective. The dot is your current setting; the faint vertical line is where the model itself sits. Notice the curve is flattest at the extremes — near a coin flip, every point of Elo moves the number most.
Where the ratings came from
Each rating is the end state of a full 2025 season of Elo updates, regressed toward the league mean for the new season.
- 2025 final rating
- 1371.0
- Regress 25% toward 1500
- +25.0
- 2026 starting rating
- 1396.0
2025 Elo trail
Biggest swings
- L 22–41 vs SF−43.9
- W 27–17 at DAL+39.3
- W 20–13 at NO+31.6
- 2025 final rating
- 1564.8
- Regress 25% toward 1500
- −13.8
- 2026 starting rating
- 1551.0
2025 Elo trail
Biggest swings
- W 41–22 at ARI+43.9
- L 26–42 vs LAR−35.5
- L 15–26 at HOU−34.7
Matchup factors
Everything beyond the two base ratings that moved this specific number.
Home field
+25.0 pts
worth 3.3 points of win probability
SF hosts at Levi's Stadium. Every host gets the same flat 25 points — the model does not rate crowds individually.
2025 head to head
- Week 3: SF won 16–15 (SF at home)
- Week 11: SF won 41–22 (SF on the road)
Strength of schedule
Who each team actually played in 2025, measured by their opponents' current ratings. This is context for reading the ratings — it is not an input to the prediction above, because beating good teams already raises a team's Elo more.
1523
average opponent rating · 2nd toughest of 32
- vs above-average teams
- 1-9
- vs below-average teams
- 2-5
1509
average opponent rating · 7th toughest of 32
- vs above-average teams
- 5-4
- vs below-average teams
- 7-1
What the model does not know
- · How an injury actually plays out — the adjustment above prices availability, not how well a replacement performs.
- · Coaching and roster turnover between seasons.
- · Weather, travel distance and short-week fatigue beyond raw rest days.
- · Anything a betting market has priced in since the season ended.