# Using the message deduplication ID in Amazon SQS
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[https://docs.amazonaws.cn/AWSSimpleQueueService/latest/APIReference/API_SendMessage.html](https://docs.amazonaws.cn/AWSSimpleQueueService/latest/APIReference/API_SendMessage.html) is a token used only in Amazon SQS FIFO queues to prevent duplicate message delivery. It ensures that within a 5-minute deduplication window, only one instance of a message with the same deduplication ID is processed and delivered.

If Amazon SQS has already accepted a message with a specific deduplication ID, any subsequent messages with the same ID will be acknowledged but not delivered to consumers.

**Note**  
Amazon SQS continues tracking the deduplication ID even after the message has been received and deleted.

**Topics**
+ [When to provide a message deduplication ID in Amazon SQS](providing-message-deduplication-id.md)
+ [Enabling deduplication for a single-producer/consumer system in Amazon SQS](single-producer-single-consumer.md)
+ [Outage recovery scenarios in Amazon SQS](designing-for-outage-recovery-scenarios.md)
+ [Configuring visibility timeouts in Amazon SQS](working-with-visibility-timeouts.md)