Can a fast speed test still have bufferbloat?

Yes. Throughput can look fine while latency climbs as soon as a download or upload fills the queue.

What should I try if latency rises under load?

Pause other transfers, enable SQM or QoS if the router offers it, and compare a wired retest. Change one thing at a time.

Bufferbloat test

Bufferbloat is extra delay that shows up when a link is full. This page runs a standard test so latency probes continue during the transfers.

Your internet speed

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Mbps·Ready

Latency
Download
Upload

Download

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Upload

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Latency

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Jitter

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Packet loss

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Not measured on this run. Use the request-loss tool for a separate check.

Server location

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Server: —
Network: —
Your IP: Unavailable

How this measurement works

Idle latency is the median of HTTP round trips before the transfer. Loaded latency is the median of probes taken about every 200 ms during download and again during upload. The increase is loaded minus idle. Letter grades use this site's documented thresholds and are not an industry certification.