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Comparison · 3 models · Updated Oct 4, 2026

Ling 3.1 Flash vs Step 5 Preview vs Laguna S 2.1

Laguna S 2.1 comes out ahead, 69 to 65 and 57 on our weighted score, though Ling 3.1 Flash is 11% cheaper per token.

  1. inclusionAI

    Ling 3.1 Flash

    Released Sep 29, 2026

    65/100
    • ECI—
    • Price$0.075 / $0.22
    • Context262K
  2. StepFun

    Step 5 Preview

    Released Sep 16, 2026

    57/100
    • ECI—
    • Price$1.00 / $2.70
    • Context1M
  3. Our pick

    Poolside

    Laguna S 2.1

    Released Jul 21, 2026

    69/100
    • ECI—
    • Price$0.10 / $0.20
    • Context1.05M
01 — Verdict

Laguna S 2.1 is our pick

Laguna S 2.1 is the better all-round choice, scoring 69/100 against Ling 3.1 Flash (65) and Step 5 Preview (57). Ling 3.1 Flash wins on price. Step 5 Preview wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceLing 3.1 FlashLing 3.1 Flash $0.111 · Laguna S 2.1 $0.125 · Step 5 Preview $1.43 per 1M tokens (3:1 blend)
  • Longest contextLaguna S 2.1Laguna S 2.1 1,048,576 · Step 5 Preview 1,000,000 · Ling 3.1 Flash 262,144 tokens
  • Widest inputsStep 5 PreviewLing 3.1 Flash: Text · Step 5 Preview: Text, Images, Video · Laguna S 2.1: Text
  • Self-hostingLaguna S 2.1Publishes downloadable weights
How the score is built
MeasureWeightLing 3.1 FlashStep 5 PreviewLaguna S 2.1
Price50%954393
Inputs & features30%358035
Context window20%376061
Overall100%65/10057/10069/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Ling 3.1 Flash vs Step 5 Preview vs Laguna S 2.1 specifications side by side
SpecificationLing 3.1 FlashinclusionAIStep 5 PreviewStepFunLaguna S 2.1Poolside
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.075 (best)$1.00$0.10
Output$0.22$2.70$0.20 (best)
Cached input—$0.05—
Blended (3:1)$0.111 (best)$1.43$0.125
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersOfficial StepFun (Global) APIMedian of 4 providers
Limits
Context window262,144 tokens1,000,000 tokens1,048,576 tokens (best)
Max output32,768 tokens1,000,000 tokens (best)32,768 tokens
Inputs and features
TextYesYesYes
ImagesNoYesNo
PDFsNoNoNo
AudioNoNoNo
VideoNoYesNo
ReasoningYesYeslow · medium · highYes
Tool callingYesYesYes
Structured outputNoYesNo
Availability
WeightsProprietaryProprietaryOpen
API model ID—step-5-previewpoolside/laguna-s-2.1
API providers37 (best)6
ReleasedSep 29, 2026Sep 16, 2026Jul 21, 2026
Knowledge cutoff———
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Ling 3.1 Flash$1.19
  • Step 5 Preview$15.40
  • Laguna S 2.1$1.40
04 — Questions

Which should you choose?

Which is better: Ling 3.1 Flash, Step 5 Preview or Laguna S 2.1?

Laguna S 2.1 is the better all-round choice, scoring 69/100 against Ling 3.1 Flash (65) and Step 5 Preview (57). Ling 3.1 Flash wins on price. Step 5 Preview wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, Ling 3.1 Flash, Step 5 Preview or Laguna S 2.1?

Ling 3.1 Flash is cheaper at $0.075 input / $0.22 output per million tokens (median across 1 API provider). Laguna S 2.1 costs $0.10 input / $0.20 output per million tokens (median across 4 API providers; free on Poolside); Step 5 Preview costs $1.00 input / $2.70 output per million tokens (official StepFun (Global) API price). At a typical mix of three input tokens to one output token, that is $0.111 per million tokens for Ling 3.1 Flash versus $0.125 for Laguna S 2.1 (1.1× as much) and $1.43 for Step 5 Preview (13× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Ling 3.1 Flash has not been scored yet, Step 5 Preview has not been scored yet and Laguna S 2.1 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for Ling 3.1 Flash, Step 5 Preview and Laguna S 2.1 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. All three support tool calling for agent workflows.

Which has the bigger context window?

Laguna S 2.1 has the largest context window at 1,048,576 tokens, against 1,000,000 for Step 5 Preview and 262,144 for Ling 3.1 Flash. Maximum output per response: Ling 3.1 Flash up to 32,768, Step 5 Preview up to 1,000,000, Laguna S 2.1 up to 32,768 tokens.

Which can read images, PDFs, audio or video?

Ling 3.1 Flash accepts text; Step 5 Preview accepts text, images and video; Laguna S 2.1 accepts text. Step 5 Preview handles the widest range of inputs.

Are any of these open source?

Laguna S 2.1 publishes its weights and can be self-hosted; Ling 3.1 Flash and Step 5 Preview is proprietary.

Which is newer?

Ling 3.1 Flash is the newest, released Sep 29, 2026. Step 5 Preview came out Sep 16, 2026; Laguna S 2.1 came out Jul 21, 2026.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.