Grok 4.3 vs Claude Opus 4.7: Aggressive Pricing vs Top Tier Capability in May 2026

xAI released Grok 4.3 on April 30, 2026. The headline change is pricing: $1.25 per million input tokens and $2.50 per million output tokens, roughly 40% cheaper on input and 60% cheaper on output than Grok 4.20. Native video input joins the lineup. Anthropic's Claude Opus 4.7, released April 16, holds the top score on SWE-bench Verified at 87.6% and SWE-bench Pro at 64.3%, with API pricing at $5 per million input and $25 per million output.

These are not models built around the same priorities. Grok 4.3 optimizes for cost per token at near frontier capability. Opus 4.7 optimizes for capability ceiling on the hardest agentic and coding tasks. Picking between them is a question of which axis dominates your workload.

The Models at a Glance

What Each Release Changed

Grok 4.3

The price cut is the most consequential change. Input pricing dropped roughly 40% and output pricing dropped roughly 60% versus Grok 4.20. xAI is positioning Grok 4.3 as a budget conscious alternative to top tier closed models, with capability close enough to the frontier to be defensible for a wide range of production workloads.

Native video input is the first time an xAI API model has processed video frames directly through a vision encoder. For workflows that need to reason over video content, Grok 4.3 is now a viable primitive without an external vision pipeline.

On benchmarks, Grok 4.3 leads CaseLaw v2 at 79.3% and CorpFin among published numbers, and posts a 1500 ELO on GDPval-AA, ahead of Gemini 3.1 Pro Preview on that metric. The Artificial Analysis Intelligence Index score of 53 trails GPT-5.5 (60), Opus 4.7 (57), and Gemini 3.1 Pro Preview (57), but the price gap to those models is large.

Opus 4.7

Opus 4.7 pushed the closed model frontier forward on agentic coding. SWE-bench Verified at 87.6%. SWE-bench Pro at 64.3%, ahead of GPT-5.4's 57.7% and Gemini 3.1 Pro's 54.2%. GPQA Diamond at 94.2%. Terminal-Bench 2.0 at 69.4%.

Pricing held at $5 / $25 per million tokens, unchanged from 4.6. The new tokenizer can produce up to 35% more tokens for the same input text, which means effective costs per request increase modestly versus prior generations despite the unchanged rate card.

Benchmark Comparison

Opus 4.7 leads on the agentic coding and graduate level reasoning benchmarks that matter most for engineering work. Grok 4.3 leads on legal and financial domain benchmarks, which reflects xAI's training emphasis on real world professional knowledge work.

For teams whose primary workload is software engineering, the benchmark gap favors Opus 4.7 by a wide margin on the published numbers. For teams whose workload is legal research, financial document analysis, or general professional knowledge work, Grok 4.3 has a stronger published case at a fraction of the cost.

Multimodal Capability

Grok 4.3 introduced native video input as an xAI first. The model processes video frames through a vision encoder without an external transcription or sampling pipeline, which simplifies the architecture for any workflow involving video content (training data analysis, content moderation, video QA).

Opus 4.7 supports text and image input. Vision quality improved sharply in 4.7 (98.5% visual acuity, 3.75MP image support), but video and audio are not native. For workflows that need video reasoning, Grok 4.3 is the only model in this comparison that handles it natively.

For high resolution image reasoning, Opus 4.7 is stronger.

Agentic Capability

This is where the gap is largest.

Opus 4.7 holds the highest published scores on SWE-bench Verified, SWE-bench Pro, and Terminal-Bench 2.0 among closed frontier models. The agentic coding tier is functionally a different class of capability than what Grok 4.3 has demonstrated on disclosed benchmarks. For multi file, multi service code editing on real repositories, Opus 4.7 is the stronger primitive by a meaningful margin.

Grok 4.3 has not published direct SWE-bench Verified or Terminal-Bench 2.0 numbers. The GDPval-AA ELO of 1500 is a strong signal on agentic professional work in non coding domains, but it is not a substitute for the published agentic coding scores Opus carries.

For teams whose core workload is engineering agents, Opus 4.7 is the default. For teams whose agents operate in legal, finance, or general knowledge work domains, Grok 4.3 is competitive at a much lower price point.

Pricing and Total Cost

At list prices, Grok 4.3 is 4x cheaper on input and 10x cheaper on output. With Opus 4.7 prompt caching applied, effective input costs land near $0.50 per million on cached tokens, which closes the input gap meaningfully on pipelines with stable system prompts. Output costs remain a 10x gap unless batch processing applies, which brings Opus output to roughly $12.50 per million.

The honest read: for high volume workloads where output tokens dominate the bill, Grok 4.3 is dramatically cheaper. For workloads where output quality compounds downstream (engineering agents, high stakes reasoning, multi step orchestration), Opus 4.7 often delivers lower total cost despite the higher per token price, because the cost of a bad output (debugging time, failed deploys, code review churn) frequently dwarfs the API bill.

Direct Comparison Table

Which One Should You Use

Use Grok 4.3 when:

• Cost per token is the dominant variable
• Native video input is a core requirement
• Your workload is legal research, financial analysis, or general professional knowledge work
• You can absorb the capability gap on agentic coding for a 4x to 10x price advantage
• You are building high volume generation pipelines where output token costs dominate

Use Opus 4.7 when:

• Agentic coding on real codebases is the core workload
• You need the highest published scores on SWE-bench Verified, SWE-bench Pro, and Terminal-Bench
• Output quality compounds downstream into measurable business impact
• Prompt caching and batch discounts materially offset the per token price
• Managed inference on Bedrock, Vertex AI, or Foundry is preferred

Use both when:

• Grok 4.3 handles high volume generation, video processing, and legal or financial analysis
• Opus 4.7 handles complex agentic work, multi file code editing, and hard reasoning
• Route by task shape rather than provider loyalty

Our Default for May 2026

For agentic coding work and the hardest reasoning tasks, Opus 4.7 is the strongest option published as of this week. The 87.6% SWE-bench Verified and 64.3% SWE-bench Pro scores are not close to any other disclosed number.

For cost sensitive high volume workloads, video input pipelines, and legal or financial domain work, Grok 4.3 is the strongest option in its price tier. The 4x input and 10x output price gap to Opus 4.7 is large enough that the routing decision becomes obvious on workloads that do not require top tier agentic coding.

These are not competing products. They are complementary primitives. A durable AI architecture in May 2026 uses Grok 4.3 where cost per token and video input matter most, and reaches for Opus 4.7 where agentic capability and output quality compound into downstream value.

How Contra Collective Bridges the Gap

Contra Collective runs Grok 4.3, Opus 4.7, GPT-5.5, Gemini 3.1 Pro, and Gemma 4 in production across coding pipelines, multimodal content systems, and multi agent workflows for enterprise clients. We architect systems that use the right model at each stage rather than defaulting to a single provider. Ready to make the right call for your stack? Book a free technical audit, no sales pitch, just clarity.