How much does Phi 4 cost?

Phi 4 costs $0.07/M input tokens and $0.14/M output tokens.

What is the context length of Phi 4?

Phi 4 has a 16,384 token context window. It supports up to 16,384 completion tokens.

Does Phi 4 support tool calling and structured outputs?

No. Phi 4 does not accept tools, so function calling is unavailable. It also supports structured outputs via a JSON schema in response_format.

Which providers serve Phi 4?

Phi 4 is served by 1 provider on OpenRouter: DeepInfra.

What other text models does Microsoft have?

Microsoft-Decision-1 is another text model from Microsoft.

When was Phi 4 released?

Phi 4 was released on January 10, 2025. Its knowledge cutoff is June 30, 2024.

Microsoft: Phi 4

microsoft/phi-4

Model weights

Compare

Microsoft Research Phi-4 is designed to perform well in complex reasoning tasks and can operate efficiently in situations with limited memory or where quick responses are needed.

At 14 billion parameters, it was trained on a mix of high-quality synthetic datasets, data from curated websites, and academic materials. It has undergone careful improvement to follow instructions accurately and maintain strong safety standards. It works best with English language inputs.

For more information, please see Phi-4 Technical Report

Modalities

In / out price

$0.07 / $0.14per 1M

Context

16K

Released

Jan 10, 2025

Knowledge cutoff

Jun 2024

Providers

Different companies host the same model. OpenRouter routes your request to one of them based on the routing mode you pick: Balanced (price + speed), Nitro (fastest), or Floor (cheapest).

Latency / throughput


	$0.07	$0.14	0.31s	80 tok/s	100.00%
Not used in Standard routing:Why these endpoints are not used
Flex	$0.056	$0.112	0.87s	97 tok/s	100.00%

Input $0.07Output $0.14
80 tok/s100.00% uptime
Not used in Standard routing:Why these endpoints are not used
Input $0.056Output $0.112
Flex
97 tok/s100.00% uptime

Pricing

The average price customers actually pay for this model, next to the prices providers post. Caching and discounts mean the price actually paid is often well below the listed one.

Weighted average

Input

$0.06915/M tokens

Output

$0.1366/M tokens

Phi 4 — Price history

Price history

No effective price data for this selection

		$0.0692	$0.137	0.0%	99.2%
Not used in Standard routing:Why these endpoints are not used
	Flex	$0.0553	$0.111	0.0%	0.8%

Effective in $0.0692Effective out $0.137
Token share
99.2%
Not used in Standard routing:Why these endpoints are not used
Effective in $0.0553Effective out $0.111
FlexToken share
0.8%

Uptime

Uptime is the percentage of the past 3 days that at least one provider was responding to requests. Availability is the percentage of time that inference was successfully served. OpenRouter continuously monitors and uses the next-best provider when one returns an error.

Uptime (3d)

100.00%

Availability (3d)

99.99%

Availability over the last 3 days

Last 72 hours

Availability 99.99%

3 Days Ago2 Days AgoYesterdayNow

Availability over the last 24 hours

OpenRouter Availability

99.99%

When an error occurs in an upstream provider, we can recover by routing to another healthy provider, if your request filters allow it. You can access per-provider uptime data programmatically through the Endpoints API. Learn more about our load balancing and provider routing options.

Benchmarks

Scores on standardized evaluations and this model’s own outputs on shared benchmark prompts. Higher percentages are better — and each rank shows where this model lands among the models evaluated on that source.

Benchmark score summary for Microsoft: Phi 4 (Artificial Analysis)
Source	Benchmark	Score
Artificial Analysis	Phi-4 GPQA Diamond	57.5%
Artificial Analysis	Phi-4 HLE	3.8%
Artificial Analysis	Phi-4 IFBench	23.5%
Artificial Analysis	Phi-4 τ²-Bench Telecom	0.0%
Artificial Analysis	Phi-4 AA-LCR	0.0%
Artificial Analysis	Phi-4 CritPt	0.0%
Artificial Analysis	Phi-4 LiveCodeBench	23.1%
Artificial Analysis	Phi-4 Terminal-Bench Hard	3.8%
Artificial Analysis	Phi-4 MMLU-Pro	71.4%
Artificial Analysis	Phi-4 AIME 2025	18.0%
Artificial Analysis	Phi-4 AIME	14.3%
Artificial Analysis	Phi-4 MATH-500	81.0%

Not currently available through EU in-region routing. In-region routing docs

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Phi-3 Medium 128K Instruct

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At time of release, Phi-3 Medium demonstrated state-of-the-art performance among lightweight models. In the MMLU-Pro eval, the model even comes close to a Llama3 70B level of performance.

For 4k context length, try Phi-3 Medium 4K.

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Microsoft: Phi 4

Providers