Fireworks AI · automatic caching

GLM 5.1

Z.ai open-weights model with strong agentic coding behaviour and balanced input/output pricing that favours output-heavy generation.

$1.40
Input / 1M tokens
$4.40
Output / 1M tokens
$0.26
Cache read · −81%
203K
Context window

Specifications

At a glance.

ProviderFireworks AI
Familyglm_moe_dsa
Released2026-04
LicenseOpen weights
Context window203K tokens
Max output131K tokens
Parameters744B
Modalitiestext
Tool callingYes
Reasoning modeYes
Cachingautomatic
Batch discountNo batch tier

Measured by Zumik

What reuse looks like here.

GLM 5.1 · agent trafficper request
Total input100%
Candidate reuse61%
Realized reuse51%
Capture rate83%
71/100
Speed score
230
Output tokens / sec
Reuse economics

What you actually pay once caching works.

At a typical 55% prefix reuse, a million input tokens on GLM 5.1 effectively costs $0.77 instead of $1.40 - blending to roughly $1.68 with a 25% output share. There is no batch tier, so cost control here leans on caching and routing.

Estimate it for your workload
Best for
codingagentictool-use

Routes through these aliases:

Call it

Same OpenAI client, this model.

python
from openai import OpenAI

client = OpenAI(base_url="https://api.zumik.ai/v1", api_key="zk_live_...")

r = client.responses.create(
    model="glm-5p1",          # or an alias like code.balanced
    input="Draft a fix for the failing test.",
)
print(r.usage.input_tokens_cached)   # confirm reuse

Frequently asked

GLM 5.1, answered.

How much does GLM 5.1 cost?

GLM 5.1 is $1.40 per million input tokens and $4.40 per million output tokens through Zumik. Cache reads are $0.26 per million, a 81% discount on input.

What is GLM 5.1's context window?

GLM 5.1 supports a 203K-token context window with up to 131K output tokens.

Does GLM 5.1 support prompt caching?

Yes. Fireworks AI uses Automatic prompt caching (serverless and dedicated) caching. In the Zumik corpus, GLM 5.1 shows a median cache capture of 83% on agent workloads.

Which Zumik aliases route to GLM 5.1?

GLM 5.1 is a candidate for the code.balanced alias, selected when it wins under current routing policy.

Run GLM 5.1 with reuse measured.

Point an OpenAI client at Zumik and see exactly how much of this model's input you are reusing.