☕ Coffee Knowledge Hub → Brewing Science | Last updated: May 28, 2026 | 8 min read
Coffee Grind Size Chart (2026)
Direct Answer: Espresso requires fine grind (200–300 microns), pour-over uses medium-fine (400–600 microns), and French press needs coarse (800–1200 microns). Grind size must match brew time: shorter contact time = finer grind. Use a burst grinder (not blade) for consistent particle size.
Grind Size by Brew Method (Complete Chart)
| Brew Method |
Grind Size (microns) |
Visual Analogy |
Extraction Time |
Burr Type |
| Turkish coffee |
100–200 μm |
Powdered sugar |
N/A (boiled) |
Ceramic / Steel conical |
| Espresso |
200–300 μm |
Table salt |
25–30s |
Steel flat or conical |
| Moka pot |
300–400 μm |
Between salt and sand |
3:00–4:00 |
Steel conical |
| Pour-over (V60) |
400–600 μm |
Coarse sand |
2:30–3:30 |
Steel conical preferred |
| Drip coffee |
500–700 μm |
Coarse sand |
4:00–5:00 |
Steel flat |
| French press |
800–1200 μm |
Sea salt / cracked pepper |
4:00+ |
Steel conical |
| Cold brew |
1000–1500 μm |
Very coarse (chunky) |
12:00–24:00 |
Steel conical |
Visual Grind Size Comparison
500 μm
Pour-over (Medium-Fine)
1000 μm
French Press (Coarse)
Why Grind Size Matters: The Physics
Coffee extraction is a diffusion process. Water dissolves soluble compounds (acids, sugars, bitter compounds) from coffee cells. The total surface area exposed to water determines extraction speed:
Surface area calculation (1g coffee):
• Fine grind (200 μm): ~2,200 cm²/g
• Medium grind (600 μm): ~730 cm²/g
• Coarse grind (1200 μm): ~370 cm²/g
Result: Fine grind extracts 3× faster than coarse grind.
Under-extraction (too coarse): Sour, salty, lacks sweetness. Caused by insufficient surface area contact.
Over-extraction (too fine): Bitter, astringent, dry finish. Caused by excessive surface area + channeling.
Burr Grinder vs. Blade Grinder
| Feature |
Blade Grinder |
Burr Grinder (Conical) |
Burr Grinder (Flat) |
| Particle uniformity |
Poor (wide distribution) |
Good (narrow distribution) |
Excellent (tighest distribution) |
| Heat generation |
High (friction) |
Low (slow rotation) |
Medium (faster rotation) |
| Price range (wholesale) |
$3–$8 |
$12–$45 |
$35–$120 |
| Espresso suitability |
❌ No |
✅ Yes (good) |
✅ Yes (excellent) |
| BonRay OEM option |
— |
✅ Yes (304 steel burrs) |
✅ Yes (316 steel burrs) |
How to Adjust Grind Size for Espresso
Espresso is the most grind-sensitive method. A change of just 50 microns can shift extraction from sour to bitter.
Step-by-step adjustment (burr grinder):
1. Start at 250 μm (finer than you think)
2. Pull a shot, note time and taste
3. If shot runs <20s → finer (reduce by 50 μm)
4. If shot runs >35s → coarser (increase by 50 μm)
5. Repeat until 25–30s, balanced flavor
6. Record the setting for this bean + roast level
Frequently Asked Questions
Q: Can I use espresso grind for pour-over?
A: No. Espresso grind (200–300 μm) will clog the filter in pour-over and cause over-extraction (bitter, astringent). Use 400–600 μm for V60 / Chemex.
Q: Why does my espresso taste sour even at fine grind?
A: Possible causes: (1) Channeling — puck prep is uneven; (2) Bean age — >6 weeks since roast, CO₂ is gone, extraction is uneven; (3) Water temperature — <90°C causes under-extraction. Fix puck prep first (WDT, proper tamp).
Q: What burr material is best for espresso grinding?
A: 316 stainless steel (corrosion-resistant, retains sharpness 3× longer than 304). Ceramic burrs stay sharp longest but are brittle (chip if a rock is present). BonRay OEM burrs: 316 steel, conical, 38mm / 48mm / 58mm diameters.
Q: How often should I clean my burr grinder?
A: Daily: Empty beans, run 5–10g of coffee to clear oils. Weekly: Brush burrs (soft brush, no water). Monthly: Full disassembly + wash (304/316 burrs are dishwasher-safe). Oily beans (dark roast) require more frequent cleaning.
Q: Can I grind finer to compensate for stale beans?
A: No. Stale beans (>8 weeks post-roast) have lost CO₂ and volatile aromatics. Grinding finer increases extraction but also increases bitter compounds (phenols, quinides) disproportionately. Use fresher beans (2–4 weeks post-roast) for best results.
*Last updated: May 28, 2026. Grind size data verified against SCA 2024 extraction standards. For OEM burr manufacturing (304/316 stainless steel), contact hello@bonrayfactory.com.*