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Comparison · 3 models · Updated Oct 4, 2026

GPT-5 Chat vs GPT-5-Codex vs Jamba Large

GPT-5-Codex comes out ahead, 42 to 34 and 30 on our weighted score.

  1. OpenAI

    GPT-5 Chat

    Released Aug 7, 2025

    34/100
    • ECI—
    • Price$1.25 / $10.00
    • Context400K
  2. Our pick

    OpenAI

    GPT-5-Codex

    Released Sep 15, 2025

    42/100
    • ECI—
    • Price$1.25 / $10.00
    • Context400K
  3. AI21 Labs

    Jamba Large

    Released Jul 1, 2025

    30/100
    • ECI—
    • Price$2.00 / $8.00
    • Context256K
01 — Verdict

GPT-5-Codex is our pick

GPT-5-Codex is the better all-round choice, scoring 42/100 against GPT-5 Chat (34) and Jamba Large (30). It leads 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 priceGPT-5 Chat and GPT-5-CodexGPT-5 Chat $3.44 · GPT-5-Codex $3.44 · Jamba Large $3.50 per 1M tokens (3:1 blend)
  • Longest contextGPT-5 Chat and GPT-5-CodexGPT-5 Chat 400,000 · GPT-5-Codex 400,000 · Jamba Large 256,000 tokens
  • Widest inputsGPT-5 Chat and GPT-5-CodexGPT-5 Chat: Text, Images · GPT-5-Codex: Text, Images · Jamba Large: Text
  • Self-hostingJamba LargePublishes downloadable weights
How the score is built
MeasureWeightGPT-5 ChatGPT-5-CodexJamba Large
Price50%242424
Inputs & features30%457035
Context window20%444436
Overall100%34/10042/10030/100

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.

GPT-5 Chat vs GPT-5-Codex vs Jamba Large specifications side by side
SpecificationGPT-5 ChatOpenAIGPT-5-CodexOpenAIJamba LargeAI21 Labs
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$1.25 (best)$1.25 (best)$2.00
Output$10.00$10.00$8.00 (best)
Cached input———
Blended (3:1)$3.44 (best)$3.44 (best)$3.50
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 2 providersMedian of 3 providersOfficial AI21 Labs API
Limits
Context window400,000 tokens (best)400,000 tokens (best)256,000 tokens
Max output128,000 tokens (best)128,000 tokens (best)4,096 tokens
Inputs and features
TextYesYesYes
ImagesYesYesNo
PDFsNoNoNo
AudioNoNoNo
VideoNoNoNo
ReasoningYesYesNo
Tool callingNoYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryOpen
API model ID——jamba-large
API providers23 (best)1
ReleasedAug 7, 2025Sep 15, 2025Jul 1, 2025
Knowledge cutoffSep 30, 2024Sep 30, 2024Aug 22, 2024
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.

  • GPT-5 Chat$32.50
  • GPT-5-Codex$32.50
  • Jamba Large$36.00
04 — Questions

Which should you choose?

Which is better: GPT-5 Chat, GPT-5-Codex or Jamba Large?

GPT-5-Codex is the better all-round choice, scoring 42/100 against GPT-5 Chat (34) and Jamba Large (30). It leads 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, GPT-5 Chat, GPT-5-Codex or Jamba Large?

GPT-5 Chat is cheaper at $1.25 input / $10.00 output per million tokens (median across 2 API providers). GPT-5-Codex costs $1.25 input / $10.00 output per million tokens (median across 3 API providers); Jamba Large costs $2.00 input / $8.00 output per million tokens (official AI21 Labs API price). At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for GPT-5 Chat versus $3.44 for GPT-5-Codex (1× as much) and $3.50 for Jamba Large (1× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. GPT-5 Chat has not been scored yet, GPT-5-Codex has not been scored yet and Jamba Large has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5 Chat, GPT-5-Codex and Jamba Large yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that GPT-5 Chat does not support tool calling, which most coding agents need.

Which has the bigger context window?

GPT-5 Chat and GPT-5-Codex have the largest context windows (400,000 and 400,000 tokens), against 256,000 for Jamba Large. Maximum output per response: GPT-5 Chat up to 128,000, GPT-5-Codex up to 128,000, Jamba Large up to 4,096 tokens.

Which can read images, PDFs, audio or video?

GPT-5 Chat accepts text and images; GPT-5-Codex accepts text and images; Jamba Large accepts text. GPT-5 Chat handles the widest range of inputs.

Are any of these open source?

Jamba Large publishes its weights and can be self-hosted; GPT-5 Chat and GPT-5-Codex is proprietary.

Which is newer?

GPT-5-Codex is the newest, released Sep 15, 2025. GPT-5 Chat came out Aug 7, 2025; Jamba Large came out Jul 1, 2025. Knowledge cutoff: GPT-5 Chat Sep 30, 2024, GPT-5-Codex Sep 30, 2024, Jamba Large Aug 22, 2024.

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.