Updated August 2026.
The IBA Manhattan is 50 ml rye whiskey, 20 ml sweet red vermouth, and one dash of Angostura — not a bourbon spec. Bourbon is a legal substitute; rye is the official grain. That 50 ml of 40% whiskey is about 1.13 NIAAA standard drinks before vermouth (~0.2 if the vermouth is 18%). This is not a 2022 top-18 tasting.
90–100 proof is the working band so the drink still tastes like whiskey after vermouth. Wheat bourbon (Maker’s) is softer; high-rye bourbon sits closer to the IBA idea. Related: bourbon Old Fashioned, rye vs bourbon, IBA drink math.
What the mixing glass actually needs
| Job | Typical bottles | Why |
|---|---|---|
| IBA default | Rye: Rittenhouse Bonded, Old Overholt Bonded, Wild Turkey Rye, Bulleit Rye | IBA writes rye. Bonded = 100 proof (27 CFR 5.88) |
| Bourbon substitute 90–100 | Buffalo Trace 90, Woodford 90.4, Wild Turkey 101, Old Forester 100 | Holds up to vermouth; identity is 27 CFR 5.143 |
| Wheat / softer Manhattan | Maker’s Mark 90, Larceny when you see it | Wheat in the flavoring-grain slot |
| Budget that still works | Evan Williams Bonded, Jim Beam Bonded | Cheap bourbon with proof |
| Skip for this drink | Honey / cinnamon whiskey, 60-proof liqueurs | Different class; sugar on vermouth |
Four IBA Manhattans at 40% whiskey + 18% vermouth are about 5.3 standard drinks. A 2-ounce whiskey pour (common US bar) is 1.33 drinks at 40% before vermouth. NIAAA binge pattern is a health line, not a target. Allocation bottles (Blanton’s, Weller) are wasted here if you only wanted caramel. Dash size: dash of bitters. Pour math: whiskey drinks.
Sources
- IBA Manhattan (fetched 2026): 50 ml rye whiskey, 20 ml sweet red vermouth, 1 dash Angostura; stir; cherry.
- TTB 27 CFR 5.143 bourbon / rye identity. Bonded = 100 proof (27 CFR 5.88).
- NIAAA standard drink (December 2025). No invented ranking or MSRP.