xAI Grok 4.3 vs SpaceXAI: Grok 4.20: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing xAI Grok 4.3 (grok-4.3) vs SpaceXAI: Grok 4.20 (x-ai/grok-4.20). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
xAI Grok 4.3 (grok-4.3) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for xAI Grok 4.3: Activate ephemeral prefix caching to slash input costs by 50% (down to $1/1M) or route via asynchronous Batch API for 50% off standard token rates.
SpaceXAI: Grok 4.20 (x-ai/grok-4.20) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for SpaceXAI: Grok 4.20: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.625/1M) or route via asynchronous Batch API for 50% off standard token rates.
In Etuki October 2026 FinOps telemetry comparing xAI Grok 4.3 (API ID: grok-4.3) vs SpaceXAI: Grok 4.20 (API ID: x-ai/grok-4.20), SpaceXAI: Grok 4.20 offers lower standard input pricing at $1.25/1M tokens ($2.5/1M output), while SpaceXAI: Grok 4.20 leads in cached prefix economics at $0.625/1M tokens (50% discount). xAI Grok 4.3 achieves a 100ms faster P90 time-to-first-token latency (180ms vs 280ms).
Enable Prompt Context Caching & Batch API to reduce repeated system prompt input token burn by 50%-97.5%.
Auto-discovered via live global telemetry registry.
| Specification / FinOps Dimension | xAI Grok 4.3 | SpaceXAI: Grok 4.20 | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | grok-4.3 | x-ai/grok-4.20 | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $2 / $10 | $1.25 / $2.5 | SpaceXAI: Grok 4.20 |
| Cache Read Price (per 1M) | $1/1M (50% Off) | $0.625/1M (50% Off) | SpaceXAI: Grok 4.20 |
| Context Window / Max Output | 512K In / 128K Out | 1953K In / 1758K Out | SpaceXAI: Grok 4.20 |
| P90 First-Token / Edge Latency | 180ms | 280ms | xAI Grok 4.3 (-100ms) |
xAI October 2026 frontier reasoning model with live X/Web grounding and sub-200ms latency.
Grok 4.20 is a reasoning model from SpaceXAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict
Real-Time Stack Cost & Hidden-Fee Simulator (MAU / Token / Egress / GMV)
Calibrated with Reddit r/FinOps & r/devops telemetry: Includes Context Caching, Bandwidth Egress, and MoR Tax
🛰️Switch from xAI Grok 4.3 to SpaceXAI: Grok 4.20
Grok 4.20 is a reasoning model from SpaceXAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict Verified P90 latency of 280ms.