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Lab tests find decaf coffee has 0 to 15 mg of caffeine per 8 oz cup, compared with about 75 to 165 mg in regular coffee.

Decaf coffee still has caffeine — lab tests find 0 to 15 mg per 8 oz cup, versus about 75 to 165 mg in a regular cup. See all 23 sourced figures, sortable.

Written by
Petra Halloran
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Published Next source check January 2027 Read 1 min

Decaf coffee is not caffeine-free. Lab tests across brands and studies put it at 0 to 15 mg per 8 oz cup, against roughly 75 to 165 mg in a regular brewed cup — a fraction most people won’t notice, though a few sensitive drinkers might. The table below holds all 23 measured figures, decaffeination methods, and regulatory thresholds sourced directly, next to regular coffee and other caffeinated drinks for scale.

Sort and compare. Click any column to sort the full set, or filter down to just decaf coffee, regular coffee, other drinks, decaffeination methods, or regulatory thresholds.

Showing 23 of 23

Caffeine Per 8 Oz Cup: Decaf Vs Regular Coffee

Decaf Coffee (Measured) Regular Coffee (Reference) Decaf brewed coffee, 10 unnamed US outlets (Phase 1) Decaf brewed coffee, 10 unnamed US outlets (Phase 1): ~0-7.0 mg ~0-7.0 mg Decaf brewed coffee, multiple US retailers Decaf brewed coffee, multiple US retailers: ~<9.0 mg ~<9.0 mg Instant decaf coffee, powder Instant decaf coffee, powder: ~2 mg ~2 mg Decaf coffee, general range Decaf coffee, general range: 2-15 mg (already 8 oz) 2-15 mg (already 8 oz) Starbucks decaf brewed, same outlet, n=6 (Phase 2) Starbucks decaf brewed, same outlet, n=6 (Phase 2): ~6.0-6.7 mg ~6.0-6.7 mg Starbucks decaf brewed, Tall (company nutrition data) Starbucks decaf brewed, Tall (company nutrition data): ~13.3 mg ~13.3 mg Dunkin' Donuts regular brewed Dunkin' Donuts regular brewed: ~71.5 mg ~71.5 mg Regular brewed coffee, general range Regular brewed coffee, general range: ~75.3-164.7 mg ~75.3-164.7 mg Starbucks Breakfast Blend, single-day purchase Starbucks Breakfast Blend, single-day purchase: ~129.5 mg ~129.5 mg Starbucks Breakfast Blend, 6-day same-store variability Starbucks Breakfast Blend, 6-day same-store variability: ~129.5-282.0 mg ~129.5-282.0 mg 0 50 100 150 200 250 300 Milligrams Of Caffeine, 0 To 300
Category Item / Brand Serving Size as Reported Caffeine Value as Reported Normalized to 8 oz (mg; ~ = calculated) Decaffeination Method Source
measured - decaf coffeeDecaf brewed coffee, 10 unnamed US outlets (Phase 1)16 fl oz0-13.9 mg~0-7.0 mgnot reportedMcCusker et al. 2006, J Anal Toxicol
measured - decaf coffeeDecaf brewed coffee, multiple US retailers16 fl oz<18 mg (upper bound reported)~<9.0 mgnot reportedMcCusker & Goldberger 2003 (UF Health press release)
measured - decaf coffeeStarbucks decaf brewed, same outlet, n=6 (Phase 2)16 fl oz12.0-13.4 mg~6.0-6.7 mgnot reportedMcCusker et al. 2006, J Anal Toxicol
measured - decaf coffeeStarbucks decaf espresso, same outlet, n=6 (Phase 2)1 shot (~1 fl oz)3.0-15.8 mgnot applicable -- espresso shot; adding water to reach 8 oz would not remove the mg of caffeine already extractednot reportedMcCusker et al. 2006, J Anal Toxicol
measured - decaf coffeeStarbucks decaf brewed, Tall (company nutrition data)12 fl oz20 mg~13.3 mgnot disclosed by StarbucksStarbucks nutrition info, via Tasting Table 2025
measured - decaf coffeeDecaf coffee, general range8 fl oz2-15 mg2-15 mg (already 8 oz)mixed/unspecifiedFDA, "Spilling the Beans" consumer update
measured - decaf coffeeInstant decaf coffee, powder1 tsp rounded (prepared, ~8 fl oz cup)2 mg~2 mgmixed/unspecifiedUSDA National Nutrient Database for Standard Reference, Legacy (2018)
measured - regular coffee (comparison)Regular brewed coffee, general range12 fl oz113-247 mg~75.3-164.7 mgn/aFDA, "Spilling the Beans" consumer update
measured - regular coffee (comparison)Starbucks Breakfast Blend, single-day purchase16 fl oz259 mg~129.5 mgn/aMcCusker & Goldberger 2003 (UF Health press release)
measured - regular coffee (comparison)Starbucks Breakfast Blend, 6-day same-store variability16 fl oz259-564 mg~129.5-282.0 mgn/aMcCusker & Goldberger 2003 (UF Health press release)
measured - regular coffee (comparison)Dunkin' Donuts regular brewed16 fl oz143 mg~71.5 mgn/aMcCusker & Goldberger 2003 (UF Health press release)
measured - regular coffee (comparison)Regular espresso, various shops40-170 mL (~1.4-5.7 fl oz)58-185 mgnot applicable -- espresso shot, not diluted to 8 ozn/aMcCusker & Goldberger 2003 (UF Health press release)
measured - other caffeinated drinkBlack tea12 fl oz71 mg~47.3 mgn/aFDA, "Spilling the Beans" consumer update
measured - other caffeinated drinkGreen tea12 fl oz37 mg~24.7 mgn/aFDA, "Spilling the Beans" consumer update
measured - other caffeinated drinkCaffeinated soft drink12 fl oz23-83 mg~15.3-55.3 mgn/aFDA, "Spilling the Beans" consumer update
measured - other caffeinated drinkEnergy drink16 fl oz54-328 mg~27.0-164.0 mgn/aFDA, "Spilling the Beans" consumer update
decaffeination method - % caffeine removedWater process (e.g. Swiss Water-style)n/a94-96% of green-bean caffeine removedn/a (process spec, not a beverage serving)Water processScientific American, "How is caffeine removed to produce decaffeinated coffee?"
decaffeination method - % caffeine removedDirect solvent (methylene chloride or ethyl acetate)n/a96-97% of green-bean caffeine removedn/a (process spec, not a beverage serving)Direct solventScientific American, "How is caffeine removed to produce decaffeinated coffee?"
decaffeination method - % caffeine removedSupercritical CO2n/a96-98% of green-bean caffeine removedn/a (process spec, not a beverage serving)Supercritical CO2Scientific American, "How is caffeine removed to produce decaffeinated coffee?"
regulatory thresholdUS -- widely cited industry figure for what counts as "decaffeinated"n/a>=97% of caffeine removed from the green bean; this exact percentage was NOT found codified as a numeric standard-of-identity in 21 CFR itself -- it's a repeated industry/consumer-media figuren/an/aConsumer Reports; Registrar Corp FDA caffeine-labeling guide
regulatory thresholdEU -- Directive 1999/4/EC, Article 2(b)n/aanhydrous caffeine content must not exceed 0.3% by weight of the coffee-based dry matter to use the label "decaffeinated" (a residual-content ceiling, not a %-removed figure like the US industry standard)n/an/aEUR-Lex, Directive 1999/4/EC
regulatory thresholdUS -- 21 CFR 173.255n/amethylene chloride solvent residue in decaffeinated roasted or instant coffee capped at 10 ppm (0.001%)n/an/a21 CFR 173.255, via Cornell Law (LII) / eCFR
regulatory thresholdEU -- methylene chloride residue limitn/acapped at 2 ppm (0.0002%)n/an/aCenter for Environmental Health, "The Deets on Decaf" (secondary summary of EU limit; EU primary text not independently fetched)

Method: ran 10+ web searches covering the McCusker/Goldberger/Cone 2006 study directly, the Starbucks espresso follow-up detail, FDA decaf labeling threshold, EU decaf labeling threshold, Swiss Water/CO2/solvent removal percentages, USDA caffeine tables, National Coffee Association citations for the 97% figure, recent (2020s) HPLC brand-comparison studies, and the FDA 'Spilling the Beans' consumer figures. Fetched every URL used as a source directly; two sites (fda.gov, registrarcorp.com) blocked the direct fetch client (404/403) and were retrieved instead via the r.jina.ai reader proxy. ecfr.gov redirected to an unblock/CAPTCHA host so 21 CFR 173.255 was sourced from Cornell Law's LII mirror instead. All 16-oz-serving figures were halved to estimate an 8-oz value; all 12-oz FDA figures were multiplied by 8/12 and the 16-oz energy-drink figure by 8/16 -- every normalized cell is marked with a leading ~. Espresso-shot figures were left as-measured since caffeine mass doesn't change with dilution.

Gaps: the 2006 study's Phase 1 tested 10 different outlets but only the abstract (via PubMed/Oxford) was accessible, so individual brand names beyond Starbucks couldn't be confirmed. No large-scale, independently sourced, serving-size-disclosed decaf caffeine comparison was found for other major chains (Dunkin', McCafe, Tim Hortons, Caribou) -- Caffeine Informer lists brand ranges but without a stated serving size, so those figures were excluded rather than guessed. No peer-reviewed, independently measured figure was found for the Swiss Water Process's specific 99.9% removal claim, which appears only on Swiss Water's own site, so the dataset instead uses Scientific American's method-class range (94-96%). No post-2006 large-sample independent lab re-test of retail decaf coffee was found, so the newest brand-level figure in this dataset is Starbucks' own 2025-referenced menu data, not an independent lab result. The EU methylene-chloride residue limit (2 ppm) is sourced from a secondary summary (Center for Environmental Health); the specific EU regulatory text setting that number was not independently fetched.

Sources