Expiry Date Calculator
Calculate when food, medicine, or any product expires — or check instantly if something has already expired given its manufacture date and shelf life.
Last updated: March 2026
How to Use the Expiry Date Calculator
- Select a preset (optional): Choose a common item from the dropdown to auto-fill the shelf life, or skip this step and enter shelf life manually.
- Enter the start date: This could be the manufacture date printed on the packaging, the purchase date, or the date you opened the product — whichever is most relevant.
- Enter the shelf life: Input the number and unit (days, weeks, months, or years). Results appear instantly — no button needed.
- Read your status: The calculator shows the expiry date, a status badge (Safe / Expiring Soon / Expired), and the percentage of shelf life remaining.
What the Results Mean
The Expiry Date Calculator gives you four key pieces of information:
- Expiry Date — The calculated date on which the product reaches the end of its shelf life.
- Status — Safe (more than 10% life remaining), Expiring Soon (within 10% of shelf life), or Expired (past the expiry date).
- Days Until Expiry — A positive number means days remaining; a negative number (shown as "X days ago") means the product is already expired.
- Percentage of Life Remaining — Useful for products you track over time, such as medications or stored food supplies.
Understanding Food Expiry Dates
Food labelling uses several different date terms, and confusing them can lead to unnecessary waste — or to consuming unsafe food. Here is what each term means:
Best Before vs. Use By vs. Sell By
Best Before refers to quality, not safety. After this date, the product may lose flavour, texture, colour, or nutritional value — but it may not be unsafe. Most dry goods, canned food, and frozen products use "best before" dates. It is often safe to consume them past this date, though quality is not guaranteed.
Use By is a food safety date. Consuming food after its "use by" date carries a genuine risk of foodborne illness, particularly for meat, fish, dairy, and ready-to-eat chilled foods. The Food Standards Agency and FDA both recommend strictly following "use by" dates — not because of taste, but because of bacterial growth that is invisible and odourless.
Sell By is a stock management date for retailers, not a consumer safety guide. Products are typically safe to consume for several days after the sell-by date if stored correctly.
Common Food Shelf Lives
- Fresh milk: 5–7 days refrigerated after opening
- Eggs: 3–5 weeks refrigerated from purchase
- Cooked leftovers: 3–4 days refrigerated
- Bread: 5–7 days at room temperature; 3 months frozen
- Dry pasta / rice: 1–2 years sealed at room temperature
- Canned vegetables: 2–5 years sealed
- Honey: Effectively indefinite if sealed and stored dry
Medicine and Cosmetic Expiry Dates
Do Medicines Expire?
Yes — all medications have expiry dates set by the manufacturer based on stability testing. Most medications remain effective and safe for a period after expiry, particularly solid oral doses like tablets and capsules stored in a cool, dry location. The US Department of Defense tested military stockpiles and found that 88% of medications remained potent 15 years past expiry — but this does not apply to all medications equally.
Never use past expiry: liquid medications, insulin, nitroglycerin, eye drops, emergency epinephrine (EpiPens), chemotherapy drugs, or antibiotics for serious infections. These may have degraded chemically in ways that are either ineffective or actively harmful.
Cosmetics and the PAO Symbol
Many cosmetics show a "Period After Opening" (PAO) symbol — an open jar with a number followed by "M" (for months). A jar marked "12M" should be discarded 12 months after first opening, regardless of the printed expiry date on the box. Products exposed to air, fingers, and varying temperatures degrade faster than sealed products. Mascara and liquid eyeliner are especially susceptible to bacterial contamination — replace every 3–6 months.
How Long Is Something Good For If Purchased On a Certain Date?
How long is milk good for after purchase?
Fresh milk is typically good for 5–7 days after the sell-by date if kept refrigerated at or below 40°F (4°C). Once opened, use within 5 days for best quality. Ultra-pasteurised (UHT) milk can last weeks unopened at room temperature but should be refrigerated and consumed within 7–10 days once opened.
How long are eggs good after purchase?
Eggs are typically safe for 3–5 weeks from the purchase date when refrigerated. You can test freshness with the float test: place the egg in a bowl of water. Fresh eggs sink and lie flat. Older but still good eggs stand upright. Floating eggs should be discarded.
How long does sunscreen last after opening?
Sunscreen is effective for approximately 1 year after opening and 2–3 years from the manufacture date. After expiry, the UV-blocking ingredients degrade and the product may no longer provide the stated SPF protection. Replace sunscreen every year, especially if stored in a hot car or beach bag.
How long does canned food last?
Most canned goods are safe for 2–5 years past the best-before date if the can is undamaged, not bulging, and stored at room temperature. High-acid canned foods (tomatoes, fruits) last 1–2 years. Low-acid foods (vegetables, meat, beans) last 2–5 years. Discard any cans that are dented, rusted, bulging, or leaking.
How long is medication safe after its expiry date?
Many tablets and capsules retain 90% or more of their potency for years past expiry if stored correctly — but this varies by medication. Never rely on expired medication for serious or life-threatening conditions. Consult a pharmacist for guidance on specific medications.
How long does bread last after purchase?
Store-bought bread lasts 5–7 days at room temperature and up to 3 months frozen. Homemade bread without preservatives typically lasts 3–4 days. Signs of spoilage include visible mould, off smell, or sliminess. Do not eat mouldy bread — the visible mould indicates widespread spore contamination throughout the loaf.
How long does opened wine last?
Opened wine typically lasts 3–5 days in the refrigerator with the cork or stopper replaced. Red wines may last slightly longer than whites. Fortified wines (port, sherry) last 1–4 weeks refrigerated. Sparkling wines go flat within 1–3 days. A wine pump vacuum preserver can extend life by a day or two.
How long do cosmetics last after opening?
Most cosmetics have a Period After Opening (PAO) symbol — an open jar marked "12M" means 12 months after opening. Mascara and liquid eyeliner should be replaced every 3 months due to bacterial contamination risk. Foundation lasts 12–18 months, lipstick 12–24 months, and pressed powder up to 2 years if kept clean.
People Also Search For
How to calculate expiry date from manufacture date
To calculate the expiry date, add the shelf life to the manufacture date. For example, if a product was manufactured on January 1 with a 12-month shelf life, it expires on January 1 of the following year. Enter both values into the calculator and it handles the arithmetic instantly.
How to check if food has expired
Check the "use by" or "best before" date printed on the packaging, then compare it to today's date. If no date is printed, use sensory checks: smell, colour, texture, and visible mould. When in doubt, throw it out — the cost of food poisoning far exceeds the cost of discarded food.
What to do with expired medicine
Do not flush expired medicine down the toilet or throw it in household rubbish. Return it to a pharmacy take-back programme or an authorised medicine disposal site. Many pharmacies accept expired medications for safe disposal. In the US, the DEA's National Prescription Drug Take Back Day provides local disposal sites twice yearly.
How to calculate shelf life percentage remaining
Shelf life percentage remaining = (days remaining / total shelf life in days) × 100. For example, if a product has a 365-day shelf life and 73 days remain, it is at 20% of its shelf life. The calculator displays this percentage automatically alongside the expiry date.
Does freezing extend expiry dates?
Yes — freezing significantly extends the safe storage period of most foods. Bread lasts 3 months frozen vs. 7 days at room temperature. Meat lasts 4–12 months frozen vs. 1–5 days refrigerated. However, freezing does not improve quality — texture and flavour may degrade over time. The printed expiry date assumes refrigerated or ambient storage, not frozen storage.
Frequently Asked Questions
How do I calculate an expiry date?
Enter the manufacture or purchase date and the shelf life (number of days, weeks, months, or years). The calculator adds the shelf life to the start date to produce the exact expiry date, then shows how many days remain or how long ago it expired.
What does 'best before' vs 'use by' mean?
"Best before" indicates peak quality — the product may still be safe after this date but quality declines. "Use by" is a food safety date — consuming the product after this date may be unsafe. Always follow "use by" dates strictly, especially for meat, dairy, and ready-to-eat foods.
How long does food last after the expiry date?
It depends on the product type and storage conditions. Dry goods can often be safely consumed weeks to months after the best-before date. Dairy, meat, and prepared foods should not be consumed after the use-by date. Refrigerated leftovers are generally safe for 3–4 days regardless of packaging dates.
How long does medicine last after its expiry date?
Most medications are safe to take shortly after expiry but may be less effective. The FDA has found that many medications retain 90% or more of their potency years after expiry if stored correctly. However, liquid medications, insulin, eye drops, and emergency medications like EpiPens should never be used past their expiry date.
Does expiry date depend on storage conditions?
Yes, significantly. Products stored in ideal conditions (cool, dry, dark places) often last longer than indicated. Heat, humidity, light, and oxygen accelerate degradation. A product stored improperly may expire before its printed date.
How do I calculate the expiry date of a product without a printed date?
If no date is printed, use the manufacture or purchase date plus the standard shelf life for that product category. The calculator includes common shelf life presets for food, medicine, and cosmetics. You can also check the manufacturer's website or product safety data sheet.
Is it safe to use sunscreen or cosmetics after expiry?
Sunscreen should not be used past its expiry date — the SPF protection degrades and may no longer shield you from UV damage. Expired cosmetics can harbour bacteria and cause skin irritation or infection. Mascara and eye products are especially risky after expiry. Most cosmetics have a Period After Opening (PAO) symbol showing months of safe use after opening.
How far in advance should I check product expiry dates?
Check medicine and first aid supplies every 6–12 months. Check pantry food items seasonally. Review cosmetics and sunscreen at the start of each season. For safety-critical products like fire extinguishers and emergency medications, set annual calendar reminders.
Why do products have different expiry dates even in the same category?
Shelf life varies based on ingredients, preservative content, processing method, packaging type, and storage requirements. Ultra-processed foods with artificial preservatives last longer than minimally processed equivalents. Vacuum-sealed packaging extends shelf life. Always read the specific product's label rather than assuming category averages apply.
What is the difference between shelf life and expiry date?
Shelf life is the duration a product remains usable — for example, "12 months." The expiry date is the specific calendar date calculated by adding the shelf life to the manufacture or start date. If a product manufactured on January 1, 2025 has a 12-month shelf life, its expiry date is January 1, 2026. This calculator converts shelf life into a specific expiry date for you.