MODELS / Z.AI

GLM 5.1

GLM-5.1 delivers a major leap in coding capability, with particularly significant gains in handling long-horizon tasks. Unlike previous models built around minute-level interactions, GLM-5.1 can work independently and continuously on a single task for more than 8…

TEXTREASONINGIMPLICIT-CACHINGREASONINGTOOL-USE
202.8K
CONTEXT WINDOW
64K
MAX OUTPUT TOKENS
$1.40
INPUT PRICE / 1M TOKENS
$4.40
OUTPUT PRICE / 1M TOKENS
QUICKSTART

Call it in one request.

OpenAI-compatible: change the base URL, and the setup is complete.

curl https://enterprise.blackbox.ai/v1/chat/completions \
  -H "Authorization: Bearer $BLACKBOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "blackboxai/zai/glm-5.1",
    "messages": [{ "role": "user", "content": "Hello!" }],
    "stream": true
  }'
SPECIFICATIONS

The full spec sheet.

Context, pricing, modalities, routing, and deployment: everything GLM 5.1 supports, in one table.

MODEL ID
blackboxai/zai/glm-5.1
DEVELOPED BY
Z.AI
MODEL TYPE
Text
RELEASED
Apr 7, 2026
CONTEXT WINDOW
202.8K
MAX OUTPUT TOKENS
64K
INPUT MODALITIES
text
OUTPUT MODALITIES
text
INPUT PRICE
$1.40 / 1M tokens
OUTPUT PRICE
$4.40 / 1M tokens
CACHE READ
$0.26 / 1M tokens
REASONING
Supported
DATA RETENTION
Standard retention
DEDICATED DEPLOYMENT
Enterprise · single-tenant
SUPPORTED PARAMETERS
max_tokenstemperaturestoptoolstool_choicereasoninginclude_reasoning