WhatsApp 24-hour window calculator.
Enter the time a customer last messaged you and see exactly when the WhatsApp customer-service window closes — with a live countdown. Inside the 24-hour window you can reply with free-form (session) messages; outside it you must re-open the conversation with a pre-approved template. Everything runs in your browser; nothing is sent anywhere.
Reflects public WhatsApp/Meta customer-service-window policy (24 hours). Meta's policies can change — confirm the current rules before you rely on them. Not affiliated with Meta.
When did the customer last message you?
The window opens the moment a customer messages you and lasts 24 hours. Times are in your device's local timezone.
Inside the window
Free-form allowedWhile the 24-hour customer-service window is open you can reply with free-form session messages — text, media, quick replies and interactive messages — with no template required.
- Send any free-form (session) message — no template needed.
- Reply with text, images, documents, audio and interactive messages.
- Every new customer reply resets the window to a fresh 24 hours.
- Ideal for live support, follow-up questions and conversational help.
Outside the window
Template requiredOnce 24 hours pass with no new customer message, free-form replies are blocked. To re-open the conversation you must send a pre-approved message template.
- Free-form (session) messages are blocked until the customer replies again.
- Use a pre-approved template (marketing, utility or authentication) to re-engage.
- When the customer replies to your template, a new 24-hour window opens.
- Template categories are priced and reviewed by Meta per its current policy.
The 24-hour clock is measured from the customer's most recent inbound message — not from the first one. Each time the customer replies, you get a fresh 24 hours of free-form messaging. If the conversation goes quiet for a full 24 hours, the window closes and you need a template to start it again.
WhatsApp message categories
Meta groups WhatsApp Business conversations into categories. The service category covers the free-form window a customer opens by messaging you; the other three are template-driven and let you start or continue conversations outside that window. Exact rules and pricing vary by market and change over time — confirm current Meta policy.
Customer-initiated conversations handled inside the 24-hour window. This is the only category where free-form (non-template) messages are allowed.
Transaction and account updates the customer expects — order confirmations, delivery updates, appointment reminders — sent via an approved utility template.
One-time passcodes and verification codes, sent via an approved authentication template with a copy-code button.
Promotions, offers, product announcements and re-engagement, sent via an approved marketing template. Requires opt-in.
The short answer
What is the WhatsApp 24-hour window?
The WhatsApp customer-service window is a 24-hour period that opens whenever a customer sends your business a message. While it is open you can reply with free-form (session) messages — any content, no template approval required. When 24 hours pass with no new inbound message the window closes, and you can only reach that customer again by sending a pre-approved message template. Every new customer reply resets the clock to a fresh 24 hours.
How the customer-service window works
The window is anchored to the timestamp of the customer's most recent inbound message. Add 24 hours to that timestamp and you have the moment the window closes. Inside that period WhatsApp treats the conversation as customer-initiated 'service' messaging, so free-form replies are allowed. Outside it, WhatsApp blocks free-form messages and requires a business-initiated template (marketing, utility or authentication) to re-open the thread. This calculator simply takes the last-message time you enter, adds 24 hours in your local timezone, and counts down the difference each second — so the timing logic is transparent and runs entirely on your device.
| Situation | What you can send |
|---|---|
| Window open (within 24h of the last inbound message) | Free-form session messages — any content, no template |
| Customer replies again | Window resets to a fresh 24 hours |
| Window closed (24h with no inbound message) | Pre-approved template only — free-form is blocked |
| Re-opening a closed conversation | Send an approved template; the customer's reply opens a new window |
| Message categories | Service (free-form) · Utility · Authentication · Marketing (templates) |
Frequently asked questions
When does the WhatsApp 24-hour window start?
It starts the moment a customer sends your business an inbound message and runs for 24 hours from that timestamp. It is always measured from the customer's most recent message, so a new reply resets the clock to a fresh 24 hours.
What can I send inside the 24-hour window?
Inside the window you can send free-form (session) messages — text, images, documents, audio and interactive messages — with no template required. Meta calls these 'service' messages.
What happens when the window closes?
Once 24 hours pass with no new inbound message, free-form messages are blocked. To reach the customer again you must send a pre-approved message template (marketing, utility or authentication). When the customer replies to your template, a new 24-hour window opens.
Does replying reset the window?
A reply from the customer resets it. Each inbound customer message restarts the 24-hour clock. Your outbound messages do not extend the window — only the customer messaging you does.
Is the window exactly 24 hours in every country?
The customer-service window is defined by Meta as 24 hours and applies broadly. Related details — such as per-message template pricing, category definitions and free entry points — vary by market and change over time, so confirm the current Meta policy for your use case.
Is this tool affiliated with WhatsApp or Meta?
No. This is a free BroadNet calculator that reflects the public WhatsApp/Meta customer-service-window policy. It is not affiliated with or endorsed by Meta, and Meta's policies can change — always confirm the current rules.
Send session messages and templates at scale through a Meta-approved BSP.
Build a template to re-open conversations outside the window — and check its structure.
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