Brewfather Recipe Build Sheet for a BJCP Style Homebrew: Grain Bill, Water Additions, Mash Steps, and Fermentation Profile

Prompt

Act as a homebrew club mentor and BJCP trained judge who builds all grain recipes in Brewfather for newer brewers. You design to the style ranges the brewer gives you, show your arithmetic so they can check it, and let Brewfather's own calculators be the final word.

Inputs:
- Style and the BJCP ranges you are designing to (OG, FG, IBU, SRM, ABV): [StyleTarget]
- Equipment (system type, batch size into fermenter, boil time, boil off, measured brewhouse efficiency): [Equipment]
- Ingredients on hand or available from the local shop: [Ingredients]
- Water report for the brewing water (Ca, Mg, Na, Cl, SO4, HCO3): [WaterReport]
- Yeast and its listed attenuation: [YeastPlan]
- Fermentation temperature control available: [FermControl]
- Output format: [Format]
- Language: [Lang]

Generate:
1. Equipment profile values to enter in Brewfather from Equipment (batch size, boil time, boil off rate, brewhouse efficiency) and a note that the recipe numbers depend on these.
2. Grain bill with weights and percentages, an estimated OG with the gravity points arithmetic, and estimated color, both checked against StyleTarget.
3. Hop schedule by addition type (boil, whirlpool or aroma, dry hop) with times and grams, and an estimated IBU for the boil additions with the formula named. Tell the brewer to adjust the bittering addition until Brewfather's IBU sits inside StyleTarget.
4. Water additions. From WaterReport, choose a target profile for the style, compute gypsum and calcium chloride grams for the total water volume, and show the resulting ions. Tell the brewer to confirm with Brewfather's water tool and its mash pH estimate.
5. Mash steps as Brewfather mash profile rows (step name, temperature, time) and why that temperature fits the style.
6. Fermentation profile as Brewfather steps (type, temperature, days) fitted to YeastPlan and FermControl, including when to dry hop and cold crash, plus estimated FG and ABV.
7. Brew day checklist with the readings to log in the batch: mash pH, pre-boil gravity, OG, volumes.

Constraints:
- Use only StyleTarget ranges the brewer provides; do not quote ranges from memory.
- Use only Ingredients listed; mark substitutions clearly.
- Label every number as an estimate; measured readings beat calculations.
- No em dashes.

Instructions

Replace every [bracket] with your details before running. Works on ChatGPT, Claude, and Gemini.

Generated Output

This image was generated using the prompt above.

Examples

Example Input

StyleTarget: BJCP 2021 18B American Pale Ale, my notes say OG 1.045 to 1.060, FG 1.010 to 1.015, IBU 30 to 50, SRM 5 to 10, ABV 4.5 to 6.2 percent
Equipment: brew in a bag, 35 L kettle, 23 L into fermenter, 60 min boil, boil off 4 L per hour, brewhouse efficiency 72 percent over my last three batches
Ingredients: pale 2-row, Munich, crystal 40L, Magnum 12 percent AA, Cascade 5.5 percent AA, Centennial
WaterReport: Ca 20, Mg 5, Na 10, Cl 15, SO4 20, HCO3 60 (ppm), total water about 30 L
YeastPlan: one 11.5 g packet of a clean American ale dry yeast, listed attenuation around 78 percent
FermControl: chest freezer with a temperature controller
Format: Brewfather style tables
Lang: English

Example Output

1. Equipment profile
Batch size 23 L | Boil time 60 min | Boil off 4 L/hr | Brewhouse efficiency 72%. If your real efficiency differs, every gravity below moves with it.

2. Grain bill
| Fermentable | kg | % |
| Pale 2-row | 4.50 | 90 |
| Munich | 0.20 | 4 |
| Crystal 40L | 0.30 | 6 |
Estimated OG: (9.92 lb x 37 + 0.44 lb x 37 + 0.66 lb x 34) x 0.72 / 6.08 gal = about 48 points, OG 1.048 (in range 1.045 to 1.060).
Estimated color: MCU 8.3, Morey about 6 SRM (in range 5 to 10).

3. Hops
| Hop | Use | Time | g |
| Magnum 12% | Boil | 60 min | 25 |
| Cascade 5.5% | Boil | 10 min | 28 |
| Cascade | Whirlpool at 80 °C | 20 min | 40 |
| Centennial | Dry hop | 3 days | 50 |
Estimated boil IBU (Tinseth): about 31 from Magnum plus about 6 from the 10 minute Cascade, about 37 total before whirlpool. Brewfather adds a whirlpool contribution based on your settings; nudge Magnum up or down a few grams until it reads inside 30 to 50.

4. Water (30 L total)
Target for a hop forward pale: sulfate forward, roughly 150 SO4 and 60 Cl.
- Gypsum 7.0 g: adds about 54 Ca and 130 SO4
- Calcium chloride (dihydrate) 2.8 g: adds about 25 Ca and 45 Cl
Result: Ca about 99, Mg 5, Na 10, Cl about 60, SO4 about 150, HCO3 60. Split salts between mash and sparge in the same ratio as the water if you sparge; for BIAB full volume, add all to the kettle. Enter these in Brewfather's water tool and check its mash pH estimate; add lactic acid only if it reads above 5.4.

5. Mash profile
| Step | Temp | Time |
| Saccharification | 66 °C | 60 min |
| Mash out | 76 °C | 10 min |
66 °C keeps the beer dry enough for the style without thinning it out.

6. Fermentation profile
| Step | Temp | Days |
| Primary | 18 °C | 5 |
| Free rise and dry hop | 20 °C | 3 |
| Cold crash | 2 °C | 2 |
Dry hop on day 5 when gravity is close to final. Estimated FG with 78% attenuation: 1.011 (in range). Estimated ABV: (1.048 - 1.011) x 131.25 = about 4.9% (in range).

7. Brew day log
- Strike volume and temperature
- Mash pH at 15 minutes
- Pre-boil volume and gravity
- Post-boil volume and OG at fermenter
- Pitch time and fermenter temperature
Enter the measured values in the Brewfather batch so your efficiency number improves for the next recipe.