How much does GLM 5.1 cost per million tokens?

GLM 5.1 costs $0.965 per million input tokens and $3.03 per million output tokens at list price, and $0.179 per million cached input tokens.

What is the context window of GLM 5.1?

GLM 5.1 accepts up to 204,800 tokens of context and returns up to 131,072 output tokens.

How much do 1,000 chat messages cost with GLM 5.1?

About $2.48, assuming 1,000 input + 500 output tokens per message.

Is there a cheaper alternative to GLM 5.1?

In the same price range, OpenAI GPT-6 Luna Pro ($0.1 / $0.5), OpenAI GPT-6 Luna ($0.1 / $0.5), Qwen Qwen3.8 Omni Flash ($0.15 / $0.47) cost less per token. Quality differs: test on your own prompts.

Where can I buy Z.ai API credits for less?

Discount credit books resell OpenRouter usage below face value within their depth, OpenRouter adds a 5.5% card fee, and Z.ai sells its own credits at face value. The live table on this page ranks them for $100 of usage.

Z.ai · live price

GLM 5.1 API pricing

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...

Mid-range ($1–5 per 1M)Tool callingReasoning

Input: $0.965; per 1M tokens
Output: $3.03; per 1M tokens
Cached input: $0.179; per 1M tokens
Context: 205K; 131K max output

List price from OpenRouter, which passes Z.ai's price through without markup. Refreshed hourly. Released April 7, 2026. Model id z-ai/glm-5.1.

What GLM 5.1 costs in practice

At list price, before any batch or caching discount.

1,000 chat messages

$2.48

1,000 input + 500 output tokens each

1,000 RAG questions

$9.23

8,000 input + 500 output tokens each

100 coding-agent steps

$3.50

30,000 input + 2,000 output tokens each, no caching

GLM 5.1 price history

No price change since we started tracking on 2026-10-01. We record prices daily; changes will show here.

GLM 5.1 price by host

14 hosts serve this model. Prices are the same or higher than list; the cheapest are first.

Baidu$0.965 in · $3.03 out · 203K ctx · 99.5% uptime 24h
StreamLake$0.966 in · $3.04 out · 200K ctx · 99.6% uptime 24h
Chutes$0.98 in · $3.08 out · 203K ctx · 84.0% uptime 24h
DeepInfra$1.05 in · $3.50 out · 203K ctx · 99.9% uptime 24h
SiliconFlow$1.19 in · $3.74 out · 205K ctx · 99.5% uptime 24h
AtlasCloud$1.26 in · $3.96 out · 203K ctx · 99.0% uptime 24h
Phala$1.21 in · $4.20 out · 203K ctx · 82.1% uptime 24h
Alibaba$1.33 in · $4.18 out · 203K ctx · 95.0% uptime 24h
Novita$1.38 in · $4.40 out · 205K ctx · 99.1% uptime 24h
Nebius$1.40 in · $4.40 out · 203K ctx · 99.7% uptime 24h
GMICloud$1.40 in · $4.40 out · 203K ctx · 99.3% uptime 24h
Friendli$1.40 in · $4.40 out · 203K ctx · 100.0% uptime 24h
Z.AI$1.40 in · $4.40 out · 203K ctx · 99.8% uptime 24h
Venice$1.40 in · $4.40 out · 200K ctx · 98.3% uptime 24h

Where to buy Z.ai credits for less

GLM 5.1 costs the same per token everywhere it's sold through OpenRouter. What changes is the price of the credits. Live quotes for $100 of usage:

#	Where you buy	You payYou pay for $100.00 of usage	vs list price	Price source
1	OrbioCardCheapest right now Credits from a discount book, plus a 5% platform fee and card processing, both included in the quote.	$85.10 incl. $2.60 card processing	-14.9%	live quote
2	smaaartCard Credits from a discount book, plus a 5% platform fee on face value. Card processing and taxes shown at checkout.	$95.00 + card processing and tax at checkout (not in this number)	-5.0%	live quote
3	Direct from the labCard Prepaid credits at face value (OpenAI, Anthropic, Google…). Taxes may apply.	$100.00 no top-up fee	list price	face value
4	OpenRouterCrypto 5% on crypto purchases. No markup on model prices.	$105.00 fees included	+5.0%	published fee
5	OpenRouterCard 5.5% on card purchases, $0.80 minimum. No markup on model prices.	$105.50 fees included	+5.5%	published fee

Disclosure: this site is run by the team behind smaaart, one of the options compared. Tables are ranked by price only, from live quotes and published fees, including when smaaart isn't first. How we compare

GLM 5.1 cost calculator

Enter your monthly tokens to price your own usage.

Model$0.965 in / $3.03 out per 1M tokens · list price, liveInput tokens / month (millions)Output tokens / month (millions)

Usage at list price$78.55/ month(quotes below are for $79.00: purchases run from $5.00 to $10,000.00)

Cheaper alternatives to GLM 5.1

Other labs' models in the same price range or the one below, cheaper per token.

Model	Input / 1M	Output / 1M	Blended 3:1	Context
OpenAI: GPT-6 Luna Pro	$0.1	$0.5	$0.2	1.1M
OpenAI: GPT-6 Luna	$0.1	$0.5	$0.2	1.1M
Qwen: Qwen3.8 Omni Flash	$0.15	$0.47	$0.23	1M
DeepSeek: DeepSeek V4.1 Flash	$0.03	$0.5	$0.147	1.0M
Qwen: Qwen3.8 Flash	$0.15	$0.47	$0.23	1M
DeepSeek: DeepSeek V4 Flash Vision Exp	$0.216	$0.647	$0.323	1.0M

Other Z.ai models

Model	Input / 1M	Output / 1M	Blended 3:1	Context
GLM 5V Turbo	$1.20	$4	$1.90	203K
GLM 5 Turbo	$1.20	$4	$1.90	203K
GLM 5	$0.6	$1.92	$0.93	205K
GLM 5.2	$1.40	$4.40	$2.15	1.0M
GLM 4.7 Flash	$0.061	$0.4	$0.145	200K
GLM 4.7	$0.6	$2.20	$1	205K

All Z.ai API prices