Vaccine Queue Calculator for Wales

How to use this Wales vaccine queue estimator

What this calculator does

This tool reconstructs the logic of the early Welsh COVID-19 vaccine queue: it assigns a historic JCVI priority group, estimates a minimum-to-maximum number of people ahead, and converts that range into a first-dose, second-dose, and post-dose planning window. It is deliberately labelled as a historical model because the original mass rollout described here took place in 2020 – 2021. It is not a current eligibility checker, booking system, medical recommendation, or promise of an appointment. For present-day vaccination information in Wales, use Public Health Wales COVID-19 vaccine guidance.

When to use it

Use the estimator when you want to reproduce a historic 2021 queue scenario, compare how age or risk-group classification affected priority, test how a different weekly first-dose capacity changes an estimated wait, or understand how assumed uptake shortened the effective queue. It is also useful for educational or retrospective analysis of the rollout sequence. Do not use it to decide whether you currently qualify for a vaccine, which product you should receive, or whether pregnancy or a health condition makes vaccination appropriate for you now.

How to calculate

1. The calculator opens with a complete demonstration: age 42, no special risk/work flags, the Welsh planning rate of 150,000 first doses per week, and 69% expected uptake. The first result and Excel workbook are available immediately.
2. Replace Age and the five Yes/No profile controls with the historical profile you want to model. Results update live.
3. Leave Vaccination rate basis on the planned rate to reproduce the default planning assumption, or choose Custom weekly rate and enter another first-dose capacity.
4. Adjust Expected uptake to test how many people in each cohort are assumed to accept vaccination. Lower uptake reduces the estimated number ahead; higher uptake increases it.
5. Read People ahead of you, Priority group, and the three date windows. Use the model checkpoints and timeline table to see the cohort totals and timing assumptions behind the headline result.
6. Select Download Excel to export the current validated model as a real XLSX workbook. Reset clears the demonstration data and results; Excel export then stays disabled until a complete valid state is entered again.

Input guide

Age is required as a whole number from 16 to 120 years; for example, 42. Higher ages generally move the profile to an earlier priority group. Decimal ages, scientific notation, negative values, or ages outside the range are rejected. Live or work in an older-adult care home? is required Yes/No; Yes maps to historic group 1 regardless of age because older-adult care-home residents and carers were prioritised first. Pregnant or planning pregnancy? is required Yes/No; in this reconstruction it changes the historical explanatory note, not the queue number by itself. Historic vaccine-product advice for pregnancy changed during 2021, so current clinical guidance must be checked separately.

Frontline health or social care worker? is required Yes/No; Yes maps to historic group 2 unless group 1 already applies. Clinically extremely vulnerable? is required Yes/No; Yes maps to historic group 4 unless a higher-priority rule applies. Underlying health condition? is required Yes/No; for ages 16 – 64, Yes maps to historic group 6 unless a higher-priority rule applies. The official 2020 JCVI priority document explains the underlying sequence and risk-based rationale in JCVI advice on COVID-19 vaccination priority groups.

Vaccination rate basis is required. The planned option uses 150,000 first doses per week, the historic Welsh planning assumption described by the source calculator. If you choose Custom, Custom weekly first-dose rate becomes required and accepts 1 to 1,000,000 doses per week, either as plain digits or correctly comma-grouped thousands such as 225,000. Expected uptake is required from 1% to 100%; 69% is the historic default. Enter a decimal point for fractions such as 72.5; decimal commas are rejected rather than silently reinterpreted.

Output guide

People ahead of you is an estimated range, not a single exact rank. The lower bound applies uptake to all estimated higher-priority cohorts; the upper bound also includes your entire assigned cohort. Priority group shows the first applicable historic rule from groups 1 through 12. The summary pills repeat the current group, first-dose rate, and uptake so assumptions remain visible. Queue before your cohort and Your cohort estimate are raw planning-population checkpoints before uptake is applied. First-dose wait converts the queue range into weeks using the selected weekly rate. Historic dose interval is 12 weeks for groups 1 – 8 and 8 weeks for groups 9 – 12, reflecting the later-2021 scheduling update embedded in the historic model.

First dose window converts the wait range into dates from an 11 January 2021 planning baseline. Second dose window adds the group-specific dose interval. Estimated protected window adds a further two-week planning marker; it is not a statement that an individual is fully immune at that date. The timeline table repeats those three milestones with earliest and latest estimates and explains the meaning of each row. A zero or very short wait can occur for the earliest priority groups; very long waits indicate a later group, high uptake, or low weekly delivery rate.

Worked example

With the startup example – age 42, no care-home, pregnancy, frontline, extreme-vulnerability, or underlying-condition flags – the historic rules assign priority group 10 (age 40 – 49). The model uses 1,620,000 people in earlier estimated cohorts and a 350,000-person group-10 cohort. At 69% uptake, the queue range is 1,620,000 × 0.69 = 1,117,800 at the lower end and (1,620,000 + 350,000) × 0.69 = 1,359,300 at the upper end. Dividing by 150,000 first doses per week gives about 7.45 – 9.06 weeks. From the 11 January 2021 model baseline, that produces the displayed first-dose window of 4 – 15 March 2021; group 10 then uses an eight-week second-dose interval.

Learn more

For historical operational context, Welsh Government archived its regular vaccine stock and distribution reports; see the Welsh Government vaccination stock and distribution archive. For the continuing programme and current clinical resources, the UK COVID-19 vaccination programme collection provides the official policy archive and current updates.