Question 1

Which LLM API is the fastest?

Accepted Answer

ModelStats monitors all major LLM APIs every 5 minutes. Gemini 2.5 Flash Lite currently has the fastest TTFT, while throughput varies by model. Check modelstats.ai for real-time data.

Question 2

What is TTFT (Time to First Token)?

Accepted Answer

TTFT measures how long it takes from sending a request to receiving the first token of the response. Lower TTFT means the model starts responding faster, which is critical for real-time applications.

Question 3

What is Inter-Token Latency (ITL)?

Accepted Answer

Inter-Token Latency is the average time between each streamed token. Lower ITL means smoother streaming output. It measures how consistently fast a model generates text.

Question 4

How does ModelStats collect performance data?

Accepted Answer

ModelStats pings every major LLM API (Claude, GPT-4, Gemini, DeepSeek) every 5 minutes with a real streaming request. We measure TTFT, total latency, inter-token latency, throughput, and error rates from actual API responses.

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