API cost decision in 10 seconds

NewKimi K3.1 Pro vs GLM 5.3 Prime

Pick Kimi K3.1 Pro when budget and context both matter.

Page updated: 2026-10-23T19:08:09Z Data confirmed: 2026-10-23T20:08:09Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Kimi K3.1 Pro when budget and context both matter.

On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $7.2 for GLM 5.3 Prime, saving $0.2 (2.8% lower).

Cost-first pickKimi K3.1 Pro

Context-first pickKimi K3.1 Pro

Sample savings$0.22.8%

10x traffic gap$2

Kimi K3.1 Pro is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $2. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Cost winner changes by workload shape: input-heavy / RAG favors Kimi K3.1 Pro, balanced workload favors GLM 5.3 Prime, and output-heavy chatbot favors GLM 5.3 Prime.

Workload shape	Token mix	Better pick	Kimi K3.1 Pro	GLM 5.3 Prime
Input-heavy / RAG	5M input + 500K output	Kimi K3.1 Pro	$15	$18.4
Balanced workload	1M input + 1M output	GLM 5.3 Prime	$12	$11.6
Output-heavy chatbot	1M input + 5M output	GLM 5.3 Prime	$52	$46.8

Cheaper input Kimi K3.1 Pro $2 vs $2.8 / 1M

Kimi K3.1 Pro is $0.8 cheaper per 1M input tokens (28.6% lower; 1.4x difference).

Cheaper output GLM 5.3 Prime $10 vs $8.8 / 1M

GLM 5.3 Prime is $1.2 cheaper per 1M output tokens (12% lower; 1.14x difference).

Larger context Kimi K3.1 Pro 1.05M vs 1M

Kimi K3.1 Pro has 48.58K more context (1.05x larger).

Sample workload Kimi K3.1 Pro $7 vs $7.2

Kimi K3.1 Pro is $0.2 cheaper on the standard workload (2.8% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Kimi K3.1 Pro Calculating… Estimated API cost

GLM 5.3 Prime Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

Kimi K3.1 Pro has the lower input price; GLM 5.3 Prime has the lower output price; Kimi K3.1 Pro offers the larger context window. For the 1M input plus 500K output sample, Kimi K3.1 Pro is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $7 for Kimi K3.1 Pro and $7.2 for GLM 5.3 Prime.

Best Fit

Choose Kimi K3.1 Pro when you care most about lower input-token price, and larger context window.

Choose GLM 5.3 Prime when you care most about lower output-token price.

Decision Notes

On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $7.2 for GLM 5.3 Prime, saving $0.2 (2.8% lower).
Kimi K3.1 Pro is $0.2 cheaper on the standard workload (2.8% lower).
Kimi K3.1 Pro is $0.8 cheaper per 1M input tokens (28.6% lower; 1.4x difference).
GLM 5.3 Prime is $1.2 cheaper per 1M output tokens (12% lower; 1.14x difference).
Kimi K3.1 Pro has 48.58K more context (1.05x larger).

Head-to-Head Specs

Feature	NewKimi K3.1 Pro (MoonshotAI)	GLM 5.3 Prime (Z.ai)
Input Price prompt tokens per 1M	$2	$2.8
Completion Price per 1M tokens	$10	$8.8
Sample Workload Cost 1M input + 500K output	$7	$7.2
Context Window	1.05M	1M
Release Date	2026-10-23	2026-09-23

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Kimi K3.1 Pro	On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $7.2 for GLM 5.3 Prime, saving $0.2 (2.8% lower).
High-volume input processing	Kimi K3.1 Pro	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GLM 5.3 Prime	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Kimi K3.1 Pro	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Kimi K2.7 Code (free) can replace Kimi K3.1 Pro when lower sample workload cost matters most: $0.
Kimi K2.6 (free) can replace Kimi K3.1 Pro when lower sample workload cost matters most: $0.
Kimi K2 0711 can replace Kimi K3.1 Pro when lower sample workload cost matters most: $1.72.
Kimi K2.5 can replace Kimi K3.1 Pro when lower sample workload cost matters most: $1.75.

Larger context near this budget

Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Llama 4 Scout offers 1.31M context with $0.25 sample workload cost.
MiMo-V2.6-Flash offers 1.05M context with $0.28 sample workload cost.

Popular competitors

DeepSeek V4.1 Flash · DeepSeek · #1
DeepSeek V4.1 Flash 1017 · DeepSeek · #2
GLM 5.3 Flash · Z.ai · #3
Hy4 preview · Tencent · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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MoonshotAI catalog

Review all tracked MoonshotAI models before deciding whether this matchup is the right shortlist.

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Z.ai catalog

Check other Z.ai models with comparable pricing, context, or release timing.

Open Z.ai models

Kimi K3.1 Pro

Kimi K3.1 Pro is Moonshot AI's flagship open-weight multimodal reasoning model and a post-trained successor to Kimi K3, with a 1M-token context window. It is built for long-horizon coding, 3D...

GLM 5.3 Prime

GLM-5.3-Prime is the high-speed variant of Z.ai's GLM-5.3, inheriting its full capabilities while delivering 1.5–2× the output throughput through inference acceleration. It supports text input and output with a 1M-token...