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Comparison · 3 models · Updated Oct 4, 2026

Command A Plus vs GPT-5.3 Chat vs Claude Opus 4.8

Too close to call on our weighted score (Claude Opus 4.8 37, Command A Plus 35, GPT-5.3 Chat 32). The right pick depends on what you value most.

  1. Cohere

    Command A Plus

    Released May 20, 2026

    35/100
    • ECI—
    • Price$2.50 / $10.00
    • Context128K
  2. OpenAI

    GPT-5.3 Chat

    Released Mar 3, 2026Deprecated

    32/100
    • ECI—
    • Price$1.75 / $14.00
    • Context128K
  3. Anthropic

    Claude Opus 4.8

    Released May 28, 2026

    37/100
    • ECI158.3
    • Price$5.00 / $25.00
    • Context1M
01 — Verdict

Too close to call

It is close. Our weighted score puts them within 2 points (Claude Opus 4.8 37/100, Command A Plus 35/100, GPT-5.3 Chat 32/100), so choose by what matters most for your work: Command A Plus on price and Claude Opus 4.8 for long inputs. 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 priceCommand A PlusCommand A Plus $4.38 · GPT-5.3 Chat $4.81 · Claude Opus 4.8 $10.00 per 1M tokens (3:1 blend)
  • Longest contextClaude Opus 4.8Claude Opus 4.8 1,000,000 · Command A Plus 128,000 · GPT-5.3 Chat 128,000 tokens
  • Widest inputsClaude Opus 4.8Command A Plus: Text, Images · GPT-5.3 Chat: Text, Images · Claude Opus 4.8: Text, Images, PDFs
  • Self-hostingCommand A PlusPublishes downloadable weights
How the score is built
MeasureWeightCommand A PlusGPT-5.3 ChatClaude Opus 4.8
Price50%19182
Inputs & features30%706080
Context window20%242460
Overall100%35/10032/10037/100

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.

Command A Plus vs GPT-5.3 Chat vs Claude Opus 4.8 specifications side by side
SpecificationCommand A PlusCohereGPT-5.3 ChatOpenAIClaude Opus 4.8Anthropic
Capability
Capabilities Index (ECI)——158.3
ECI rank——#12 of 148
GPQA DiamondGraduate-level science questions——91.0%
FrontierMath Tiers 1–3Research-level mathematics——80.0%
OTIS Mock AIME 2024–2025Competition mathematics——98.3%
SimpleQA VerifiedShort factual questions——53.0%
Price per million tokens
Input$2.50$1.75 (best)$5.00
Output$10.00 (best)$14.00$25.00
Cached input—$0.175 (best)$0.50
Blended (3:1)$4.38 (best)$4.81$10.00
Long-context rateSame rateSame rateSame rate
Price sourceOfficial Cohere APIOfficial OpenAI APIOfficial Anthropic API
Limits
Context window128,000 tokens128,000 tokens1,000,000 tokens (best)
Max output64,000 tokens16,384 tokens128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoNoYes
AudioNoNoNo
VideoNoNoNo
ReasoningYesNoYeslow · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsOpenProprietaryProprietary
API model IDcommand-a-plus-05-2026gpt-5.3-chat-latestclaude-opus-4-8
API providers1445 (best)
ReleasedMay 20, 2026Mar 3, 2026May 28, 2026
Knowledge cutoffApr 1, 2025Aug 31, 2025Jan 2026
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.

  • Command A Plus$45.00
  • GPT-5.3 Chat$45.50
  • Claude Opus 4.8$100.00
04 — Questions

Which should you choose?

Which is better: Command A Plus, GPT-5.3 Chat or Claude Opus 4.8?

It is close. Our weighted score puts them within 2 points (Claude Opus 4.8 37/100, Command A Plus 35/100, GPT-5.3 Chat 32/100), so choose by what matters most for your work: Command A Plus on price and Claude Opus 4.8 for long inputs. 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, Command A Plus, GPT-5.3 Chat or Claude Opus 4.8?

Command A Plus is cheaper at $2.50 input / $10.00 output per million tokens (official Cohere API price). GPT-5.3 Chat costs $1.75 input / $14.00 output per million tokens (official OpenAI API price); Claude Opus 4.8 costs $5.00 input / $25.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $4.38 per million tokens for Command A Plus versus $4.81 for GPT-5.3 Chat (1.1× as much) and $10.00 for Claude Opus 4.8 (2.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. Command A Plus has not been scored yet, GPT-5.3 Chat has not been scored yet and Claude Opus 4.8 has an ECI of 158.3.

Which is better for coding?

There are no published SWE-bench Verified results for Command A Plus, GPT-5.3 Chat and Claude Opus 4.8 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?

Claude Opus 4.8 has the largest context window at 1,000,000 tokens, against 128,000 for Command A Plus and 128,000 for GPT-5.3 Chat. Maximum output per response: Command A Plus up to 64,000, GPT-5.3 Chat up to 16,384, Claude Opus 4.8 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Command A Plus accepts text and images; GPT-5.3 Chat accepts text and images; Claude Opus 4.8 accepts text, images and PDFs. Claude Opus 4.8 handles the widest range of inputs.

Are any of these open source?

Command A Plus publishes its weights and can be self-hosted; GPT-5.3 Chat and Claude Opus 4.8 is proprietary.

Which is newer?

Claude Opus 4.8 is the newest, released May 28, 2026. Command A Plus came out May 20, 2026; GPT-5.3 Chat came out Mar 3, 2026. Knowledge cutoff: Command A Plus Apr 1, 2025, GPT-5.3 Chat Aug 31, 2025, Claude Opus 4.8 Jan 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.