Record every grain, sugar and fruit wash batch. Saved in your browser — no account needed.
Consistency is the difference between a repeatable recipe and a lucky batch. A mash log lets you track every variable that affects fermentation performance — grain ratios, water chemistry, yeast health, temperature and timing — so you can reproduce your best results and diagnose problems when something goes wrong.
Whether you are brewing a grain mash, running a simple sugar wash, or fermenting a fruit base for brandy, recording OG and FG lets you calculate actual ABV and understand how close your yeast came to its theoretical limit. Over time your log becomes a reference library of what works in your setup.
A complete log entry covers four areas: the recipe (grain bill or sugar additions, water volume, any nutrients), the gravity readings (OG at pitch, FG at completion), the yeast profile (strain, pitch rate, pitch temperature, fermentation temperature), and observations (colour, clarity, fermentation activity, any off-aromas). The notes field is where you capture what the numbers cannot — what the wash smelled like on day three, whether fermentation was sluggish, or what you would change next time.
Even partial entries are valuable. An OG reading with no FG is still useful for cross-referencing with your distillation log later.
A grain mash requires mashing enzymes to convert starches to fermentable sugars before yeast can act. Strike temperature, mash temperature and mash time all affect conversion efficiency and the flavour profile of the wash. Logging these parameters lets you track how small changes in mash temperature shift the ratio of fermentable to unfermentable sugars.
A sugar wash is simpler: sucrose or dextrose dissolves directly, and fermentation is primarily a function of sugar concentration, yeast nutrition and temperature. The key variables to track are sugar weight, wash volume (which determines OG), yeast strain and nutrient additions.
A fruit wash introduces natural sugars, wild yeast risk and variable pH. Recording fruit weight, added sugar, and any sulphite or nutrient additions gives you the context to understand why one batch fermented cleanly and another did not.
Yes. All entries are saved entirely in your browser using localStorage. No data is sent to any server. DistilCalc has no access to your log entries. The data is stored only on the device and browser you use — it will not appear if you open the page on a different device or in a different browser.
Use the Export CSV or Export JSON buttons in the saved batches panel. CSV opens directly in Excel or Google Sheets for easy review. JSON can be imported back if you need to move entries to another device. Export regularly — clearing browser data or switching browsers will erase your entries.
The log auto-calculates ABV using the standard formula: ABV = (OG − FG) × 131.25. For example, OG 1.060 and FG 1.002 gives (0.058) × 131.25 = 7.61% ABV. This formula is accurate within ±0.3% for most home fermentations up to about 12% ABV. For higher-gravity washes use the Fermentation ABV Calculator for a more precise result.
Yes — use the same batch name in both logs. In the Distillation Log, the Linked Batch field is a free-text reference. If you name your mash "Corn Mash #4" here, enter the same name in the distillation log entry to connect the records.
For a sugar wash targeting 10% ABV, aim for OG 1.075–1.080. For 14% ABV, OG around 1.100–1.105. Higher OGs stress yeast and risk a stuck fermentation — always add adequate nutrients (DAP, Fermaid-O or similar) and keep fermentation temperature in the yeast's recommended range.
In-depth guides written for home distillers and craft producers — from reading a hydrometer to making clean spirit cuts.