What changed in Grok 4.6 vs Grok 4.5?

Grok 4.6, launched August 7, 2026, reuses the same 1.5-trillion-parameter V9 foundation as Grok 4.5 but ships with significantly improved supervised fine-tuning (SFT) and reinforcement learning (RL). The changes target Grok 4.5's high hallucination rate and aim for better instruction following, cleaner code, and steadier reasoning — while preserving Grok 4.5's speed and token efficiency.

Is Grok 4.6 worth upgrading to from Grok 4.5?

If Grok 4.5's hallucinations or instruction-following were pain points, yes — Grok 4.6's post-training upgrades directly target those, at the same speed and token efficiency. But as of August 11, 2026, xAI has not published official comparative benchmarks, so the gains are qualitative for now. It's a drop-in swap on the same foundation, so upgrading is low-risk.

How much does Grok 4.6 cost?

As of August 11, 2026 xAI has not published an official Grok 4.6 model card or pricing. Grok 4.5 is $2 input / $6 output per million tokens — the cheapest frontier tier, about 2.5x cheaper than GPT-5.6 Sol and Claude Opus 5 — and Grok 4.6 is expected to hold that pricing since it shares the foundation.

Quick Answer

Grok 4.6 vs Grok 4.5: Should You Upgrade? (Aug 2026)

Published: August 11, 2026

The Short Answer

Grok 4.6 launched August 7, 2026 on the same 1.5T V9 foundation as Grok 4.5, with upgraded SFT and RL rather than a bigger model. It targets Grok 4.5’s hallucination rate and instruction-following while keeping the same speed and token efficiency. It’s a low-risk, same-price upgrade — but as of August 11, 2026, no official head-to-head benchmarks yet.

What Actually Changed

Grok 4.6 is a post-training release, not a new base model. Concretely, xAI’s SFT/RL upgrades aim for:

Lower hallucination rate — Grok 4.5’s ~54% hallucination figure was its biggest complaint; 4.6 targets it directly.
Better instruction following and cleaner code generation.
Steadier reasoning on multi-step tasks.
Preserved speed and token efficiency — no cost or throughput penalty.

Grok 4.5 Baseline (What You’re Upgrading From)

Grok 4.5 (July 8, 2026) scored 54 on the Artificial Analysis Intelligence Index, 64.7% on SWE-Bench Pro, and 83.3% on Terminal-Bench 2.1. On Snorkel’s GDPval+ professional-work set it hit a 29% mean pass rate, ahead of GPT-5.5 (22%) and Opus 4.8 (21%) — with notably high token efficiency.

Pricing

Grok 4.5 is $2 in / $6 out per MTok — the cheapest frontier tier, ~2.5x cheaper than GPT-5.6 Sol ($5/$30) and Claude Opus 5 ($5/$25). xAI hasn’t published a Grok 4.6 card or price as of August 11, 2026, but expect parity given the shared foundation.

Should You Upgrade?

Yes if hallucinations or sloppy instruction-following bit you on 4.5 — the upgrade is drop-in and free of speed/cost penalty.
Wait for benchmarks if you need proof: independent evals (Arena.ai and others) were expected the week after the Aug 7 launch.

The Reality Check

Grok 4.6 is a quality refinement, not a leap. For hardest-problem coding and agentic work, Claude Opus 5 and GPT-5.6 Sol still lead the accuracy tables; Grok’s play is frontier-adjacent quality at the lowest price.

Sources

Kie.ai — What Is Grok 4.6 (1.5T V9, launched Aug 7, 2026): kie.ai
Snorkel — Grok 4.5 professional-work testing (GDPval+): snorkel.ai
xAI — release notes: x.ai