API cost decision in 10 seconds

NewGLM 5.3 Prime vs Laguna S 2.1 (free)

Pick Laguna S 2.1 (free) for lower cost; pick GLM 5.3 Prime only if the larger context window matters more.

Page updated:  Data confirmed:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Laguna S 2.1 (free) for lower cost; pick GLM 5.3 Prime only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Laguna S 2.1 (free) is estimated at $0 vs $7.2 for GLM 5.3 Prime, saving $7.2 (100% lower).

Cost-first pickLaguna S 2.1 (free)
Context-first pickGLM 5.3 Prime
Sample savings$7.2100%
10x traffic gap$72

GLM 5.3 Prime has more context, but Laguna S 2.1 (free) saves $7.2 on the standard workload. At 10x that traffic, the same price gap is about $72. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Laguna S 2.1 (free) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickGLM 5.3 PrimeLaguna S 2.1 (free)
Input-heavy / RAG5M input + 500K outputLaguna S 2.1 (free)$18.4$0
Balanced workload1M input + 1M outputLaguna S 2.1 (free)$11.6$0
Output-heavy chatbot1M input + 5M outputLaguna S 2.1 (free)$46.8$0
Cheaper input Laguna S 2.1 (free) $2.8 vs $0 / 1M

Laguna S 2.1 (free) is free for input tokens while GLM 5.3 Prime costs $2.8 per 1M tokens.

Cheaper output Laguna S 2.1 (free) $8.8 vs $0 / 1M

Laguna S 2.1 (free) is free for output tokens while GLM 5.3 Prime costs $8.8 per 1M tokens.

Larger context GLM 5.3 Prime 1M vs 262.14K

GLM 5.3 Prime has 737.86K more context (3.81x larger).

Sample workload Laguna S 2.1 (free) $7.2 vs $0

Laguna S 2.1 (free) is free for the standard workload while the other model is estimated at $7.2.

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
GLM 5.3 Prime Calculating… Estimated API cost
Laguna S 2.1 (free) 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

Laguna S 2.1 (free) has the lower input price; Laguna S 2.1 (free) has the lower output price; GLM 5.3 Prime offers the larger context window. For the 1M input plus 500K output sample, Laguna S 2.1 (free) is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $7.2 for GLM 5.3 Prime and $0 for Laguna S 2.1 (free).

Best Fit

Choose GLM 5.3 Prime when you care most about larger context window.

Choose Laguna S 2.1 (free) when you care most about lower input-token price, and lower output-token price.

Decision Notes
  • On the standard 1M input plus 500K output workload, Laguna S 2.1 (free) is estimated at $0 vs $7.2 for GLM 5.3 Prime, saving $7.2 (100% lower).
  • Laguna S 2.1 (free) is free for the standard workload while the other model is estimated at $7.2.
  • Laguna S 2.1 (free) is free for input tokens while GLM 5.3 Prime costs $2.8 per 1M tokens.
  • Laguna S 2.1 (free) is free for output tokens while GLM 5.3 Prime costs $8.8 per 1M tokens.
  • GLM 5.3 Prime has 737.86K more context (3.81x larger).
Head-to-Head Specs
FeatureNewGLM 5.3 Prime
(Z.ai)
Laguna S 2.1 (free)
(Poolside)
Input Price
prompt tokens per 1M
$2.8$0
Completion Price
per 1M tokens
$8.8$0
Sample Workload Cost
1M input + 500K output
$7.2$0
Context Window1M262.14K
Release Date

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionLaguna S 2.1 (free)On the standard 1M input plus 500K output workload, Laguna S 2.1 (free) is estimated at $0 vs $7.2 for GLM 5.3 Prime, saving $7.2 (100% lower).
High-volume input processingLaguna S 2.1 (free)Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsLaguna S 2.1 (free)Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGLM 5.3 PrimeA larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps
  • GLM 5.2 (free) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.
  • GLM 4.5 Air (free) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.
  • GLM 4 32B can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.15.
  • GLM 5.3 Flash (batch) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.16.

Cheaper alternatives

Review low-cost models sorted by a standard 1M input plus 500K output workload.

Open cheapest models

Larger context alternatives

Find models with larger context windows for RAG, long documents, and codebase review.

Open largest context models

Provider catalogs

Compare models within provider hubs before choosing a final API vendor.

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Z.ai catalog

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

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Poolside catalog

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

Open Poolside models
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...

Laguna S 2.1 (free)

Laguna S 2.1 is the latest coding agent model from [Poolside](<https://poolside.ai/>). Laguna S 2.1 is a 118B total parameter model with 8B active parameters, scoring 70.2% on Terminal-Bench 2.1 and...