Choose by question

Find the right caffeine tool

CaffCalc separates quick dose calculations, daily planning and source-backed drink data. Choose the question closest to yours; every timing result uses the same transparent half-life model.

Not sure where to start?If you already know the dose, use the caffeine remaining calculator. If you have several drinks and a bedtime, use the multi-drink calculator.

Calculate one dose Combine several drinks

Choose your next drink

Build an order, compare a bedtime target or find a lower-caffeine swap.

Coffee shop calculator

Build a documented Starbucks or Costa UK order with size and extra-shot estimates.

What can I drink now?

Find servings that fit your chosen estimated bedtime target.

Caffeine swap tool

Compare lower-caffeine alternatives to your usual drink.

Weekly caffeine report

Explore seven completed days of your private tracker history.

Timing

Estimate what remains and explore how dose, time and half-life change the result.

Caffeine remaining calculator

Start with any dose and see what may remain after a chosen number of hours.

Before-bed calculator

Estimate the contribution of one or more drinks at your planned bedtime.

Half-life calculator

Compare faster, central and slower caffeine-clearance scenarios.

Wear-off calculator

Estimate when a combined total may fall below reference levels.

Daily planning

Plan a decision, record drinks privately or audit a typical day.

Caffeine planner

Test another drink, work backwards from bedtime or compare two plans.

Daily caffeine tracker

Log drinks on this device and view an estimated live curve and seven-day pattern.

Daily intake calculator

Add every serving in a typical day and identify the largest contributors.

Multi-drink caffeine calculator

Combine several doses and calculate an estimated bedtime total and timeline.

Cutting down

Turn a measured starting point into a transparent comparison or gradual plan.

Caffeine taper calculator

Create an adjustable step-down schedule from a current daily total.

Half-caf calculator

Work out a full-caf and lower-caf blend for a chosen target.

Drink data

Find a documented serving first, then carry that value into a calculator or tracker.

Caffeine database

Search named drinks, serving sizes, markets and evidence quality.

Compare drinks

Compare two documented servings and their estimated timelines.

UK caffeine database

Browse the source-backed UK dataset and download it as CSV or JSON.

UK brand guides

Check which figures are first-party and which are clearly flagged as weaker evidence.

Educational estimates, not personal medical adviceCaffCalc models exponential caffeine clearance. It cannot measure caffeine in your body or predict sleep, and it does not define a safe personal dose. Sources and limitations remain visible beside the relevant data and results.