Your everyday pour-over tastes good. Then someone asks for a cup, so you double the coffee and water. The larger brew takes longer, fills the dripper higher, and tastes different from the one you know.

The arithmetic was right. The brewing conditions changed.

To scale a pour-over recipe, preserve the coffee-to-water ratio first, check that the batch fits your equipment, then adjust the brewing process by observation and taste. You are creating a larger version of a familiar drink, not multiplying every setting by the same number.

Keep the coffee to water ratio first

Use the ratio from a recipe you already enjoy. A 1:16 ratio means 16 grams of brewing water for every gram of dry coffee. Moving from 15 grams of coffee to 30 grams changes the water allowance from 240 to 480 grams.

Brewing water = dry coffee dose × ratio number

If you know the water amount instead, divide it by the ratio number. At 1:16, a 400-gram water allowance calls for 25 grams of coffee.

Dry coffee	Total brewing water at 1:16	Example bloom at 3 times the dose	Water remaining after bloom
15 g	240 g	45 g	195 g
20 g	320 g	60 g	260 g
25 g	400 g	75 g	325 g
30 g	480 g	90 g	390 g

The bloom is included in the total, not added on top. Three times the dose is an illustrative bloom allowance here, not a requirement for every method.

These water amounts are inputs, not promised drink weights. Some liquid remains in the wet grounds and filter. If you need two full mugs, check the actual beverage yield of your familiar recipe rather than assuming 480 grams of brewing water produces 480 grams in the server. Barista Hustle on beverage weight

Check the dripper and receiving vessel

Before grinding more coffee, check the brewer's recommended range and use the matching filter. Hario, for example, lists its ceramic V60 02 for one to four cups and defines a cup as 120 milliliters on its Japanese product page. That is not the same as four large mugs. Hario V60 size and cup specifications

Leave room for both the coffee bed and water above it. A dripper that holds the dry grounds can still become crowded during pouring. Check the server's usable capacity too, and make sure the kettle can supply the planned water without a mid-brew refill.

Include the server, dripper, grounds, and brewing water when checking your scale's load limit. Taring changes the displayed reading; it does not increase the scale's capacity.

If the setup is cramped, two familiar smaller brews may be simpler than forcing one oversized batch.

Expect the coffee bed to change

Adding coffee to the same dripper makes a deeper bed. In a cone, its width also changes as the coffee sits higher. Keeping a 1:16 ratio does not preserve the geometry that water travels through.

Barista Hustle explains that bed depth affects contact time and that excessively deep beds can slow brewing. This is why scaling has a physical limit, even when the recipe calculator keeps producing sensible numbers. Coffee bed depth and batch size

Depth is not the only influence. Grind, filter resistance, and the water level above the bed also affect flow. More water above the grounds increases the driving pressure, so you cannot predict the new finish time from dose alone. How water flows through a coffee bed

For a modest increase that fits the brewer, your familiar grind is a useful first reference. Observe what happens before making a large adjustment.

Plan the pours without doubling the clock

Pour size and pouring speed are different variables. Delivering 100 grams in 20 seconds averages 5 grams per second. Delivering 200 grams in those same 20 seconds requires 10 grams per second. You have doubled the stream's average delivery rate, not merely the recipe quantity.

Nor must a larger brew take twice as long. Broadsheet's pour-over guide gives a 3:15–3:45 finish range for its 30-gram recipe. For smaller 20–24-gram batches, it suggests 2:45–3:15 and explicitly calls for adjusting grind and pour times and amounts. Those windows belong to that method, but the approach is useful: adapt the process instead of multiplying a deadline. Broadsheet's batch-size adjustments

For your own scaled recipe, calculate the pour weights in advance. Keep the water level manageable and note the pauses you actually use. Do not force twice the water through the same schedule if it floods the filter.

Try a measured larger batch

Suppose your baseline is 15 grams of coffee with 240 grams of water, and you want to try 30 grams with 480 grams. The following is a starting framework for a dripper that comfortably accommodates the larger dose, not a replacement for a brewer-specific recipe.

1. Keep the comparison familiar. Use the same coffee, water, filter type, and kettle temperature. Rinse the paper as usual and discard that water before adding the coffee.
2. Set up the scale. Place the server, dripper, filter, and 30 grams of ground coffee on it. Tare the complete assembly before pouring. The cumulative reading will track water added, approximately, while everything stays on the scale.
3. Bloom with 90 grams. Start the timer with the first water and wet the bed evenly. Use your familiar bloom duration for the first trial; doubling the dose does not automatically call for doubling the wait.
4. Add the remaining 390 grams. One simple division is three 130-gram pours, taking the cumulative reading to 220, 350, and 480 grams. Pause as needed for headroom, keep the stream controlled, and record those pauses. Do not tare between pours.
5. Record and compare. Note the final pour's end time and the brew's finish. Remove the dripper, gently mix the coffee, and taste at a comfortable temperature. Compare with your baseline at a similar temperature.

The pour targets make the water accounting repeatable. They do not prescribe how fast your particular coffee should drain.

Adjust one variable at a time

If the larger batch repeatedly drains poorly and tastes unpleasantly drying, try a small move coarser while holding the new dose and water total steady. Grind changes the bed's resistance, while very fine particles can also restrict the filter. Grind and drainage

If water accumulates because pours arrive too quickly, revise the spacing before assuming the grind is wrong. If the cup is enjoyable despite a longer finish, there may be nothing to fix.

For a smaller batch that runs quickly and tastes weak or incomplete, a slightly finer setting can be a useful test. Treat the result as evidence, not a rule that small batches always need fine grinding or large batches always need coarse grinding.

Keep the ratio fixed while investigating these changes. Altering dose, water, grind, and pouring together makes it difficult to identify what helped.

Save each batch size as its own recipe

Once the larger brew tastes good, record its dose, total water, bloom, cumulative pour targets, grind setting, temperature, and timing. Give it a clear name such as “30 g sharing recipe” instead of remembering it as “the usual recipe doubled.”

Keep the smaller version too. Scaling back down may need the original grind and pouring pattern rather than the settings you settled on for the larger bed.

The ratio gives you a starting quantity. A recipe you can repeat also describes how that water reaches the coffee. Preserve the first, then learn the second for each batch size you actually brew.