TDS for Pour-Over Coffee: Measure Then Repeat

Pour-over coffee rewards precision, and TDS (Total Dissolved Solids) is your measurable key to unlocking cafe-level consistency at home. By quantifying what's in your cup (typically 1.15% to 1.55% dissolved coffee solids for optimal pour-over), you turn guesswork into repeatable results. This guide cuts through the noise with a data-backed framework for dialing in your brew, tackling water variability, grinder quirks, and weekday time constraints head-on. Control the variable you can taste: measure, log, then repeat. Here's how to leverage TDS for precision brewing without overhauling your routine.

FAQ: TDS for Pour-Over Coffee

What is TDS and why does it matter for pour-over?

TDS measures the concentration of dissolved coffee solids in your brew, expressed as a percentage. For example, a TDS of 1.3% means 1.3% of your cup is coffee compounds, while the rest is water. This metric directly impacts strength and balance:

Low TDS (under 1.15%): Weak, sour, or hollow cups from underextraction
High TDS (over 1.55%): Bitter, astringent flavors from overextraction
Optimal range (1.15-1.55%): Balanced sweetness and clarity

For pour-over, TDS matters because it quantifies what your palate detects. When your tap water hardness shifts or grind consistency wavers, TDS readings can flag inconsistencies before taste does. For a deeper dive into how variables drive extraction, see our pour-over extraction science guide.

How do I measure TDS accurately at home?

You'll need a refractometer (≈$100-$200) and a disciplined process:

Calibrate: Use distilled water to zero the device before each session.
Prepare your sample: Cool brewed coffee to 20°C (68°F). Stir vigorously to homogenize.
Measure: Place 3-4 drops on the prism. Close the lid, wait 10 seconds, then read TDS. Repeat 3x for reliability.
Clean: Wipe with an alcohol swab immediately after use.

Pro tip: Log TDS alongside brew variables (grind size, water temp, pour time). After 5 brews, patterns emerge (for example, a 10 µm finer grind raises TDS by ≈0.08%).

What’s the ideal TDS range for pour-over?

Target 1.15-1.55% TDS for balanced extraction. This sweet spot adapts to your preferences:

Brew Style	Target TDS	Flavor Profile
Light Nordic roasts	1.15-1.35%	Highlight acidity, floral notes
Medium roast	1.3-1.45%	Balanced sweetness/body
Bold/dark roasts	1.4-1.55%	Enhance body, mute bitterness

Why this range? It syncs with the Specialty Coffee Association's pour-over water standard (75-250 ppm minerals), which enables extraction without scaling equipment or muddying clarity. If your tap water misses that range, use our pour-over water quality guide to fix minerals fast.

How do I adjust my brew to hit target TDS?

Fix off-target TDS by manipulating one variable per brew. Hold others constant:

TDS too low (<1.15%): Increase extraction via finer grind (+10-20 µm), hotter water (+2-4°C), or extended bloom (15-30 s longer).
TDS too high (>1.55%): Reduce extraction with coarser grind, cooler water (88-92°C), or faster pours to shorten contact time.

Weekday shortcut: When TDS drifts, adjust grind size first (it impacts extraction most directly). Dial in one reliable bean/roast combo, then log settings for 5-minute reproducibility. To refine grind precisely by brewer, see our grind size dialing guide.

What common TDS pitfalls sabotage pour-over?

Inconsistent water: Tap TDS swings daily. Measure yours monthly; if >250 ppm, use a filter. If <75 ppm, add minerals (e.g., 10-20 ppm Epsom salt).
Ignoring extraction yield (EY): TDS alone is incomplete. Calculate EY for full context: EY (%) = (TDS × Brewed Coffee Weight) / Coffee Dose × 100. Aim for 18-22% EY.
Chasing "perfect" numbers: TDS is a compass, not the destination. If a 1.45% TDS brew tastes stellar but misses your 1.5% target by 0.05%, trust your palate.

Can I improve TDS consistency without expensive gear?

Yes. Prioritize these low-cost controls:

Use a gooseneck kettle: Steady pours minimize channeling, stabilizing extraction. Not sure which kettle to pick? Start with our gooseneck kettle comparison for precise pouring control.
Weigh everything: Dose (±0.1 g) and water (±1 g) variance skews TDS.
Fix water first: Test tap TDS with a $20 meter. If outside 75-250 ppm, use Third Wave Water or a Brita filter.

Legacy solution: No refractometer? Stick to a tight recipe: 15 g coffee, 250 g water, 93°C, 3:00 total brew time. Adjust grind by taste only.

TDS mastery turns pour-over into a repeatable ritual (not a daily experiment). Measure your baseline, tweak deliberately, and log to lock in gains. Control the variable you can taste, and your weekday cup will mirror your weekend best.