DeepSeek V4 vs Grok Code Fast 1

DeepSeek · China  |  xAI · US · Updated June 2026

Quick verdict

Pick DeepSeek V4 for near-frontier coding at ~1/12 the cost or open mit-licensed weights you can self-host. Pick Grok Code Fast 1 for fast, cheap agentic coding at $0.20/$1.50 or low-latency code generation and terminal tasks. Choose DeepSeek V4 if you need self-hosting or data privacy; Grok Code Fast 1 if you want a managed API.

DeepSeek V4 (DeepSeek, China) and Grok Code Fast 1 (xAI, US) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. DeepSeek V4 is china's open-weight price earthquake — near-frontier capability at roughly a twelfth of GPT-5.5's cost. Grok Code Fast 1 is xAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecDeepSeek V4Grok Code Fast 1
ProviderDeepSeek (China) xAI (US)
ReleasedApril 24, 2026 August 28, 2025
Context window1M (~1,500 pages) 256K (~384 pages)
Price (in/out)$0.435/$0.87 per 1M tokens $0.2/$1.5 per 1M tokens
Open weight?Yes — self-hostable No — API only
Modalitiestext, code text, code
SWE-Bench Verified80.6% Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Near-frontier coding at ~1/12 the cost

DeepSeek V4

Grok Code Fast 1 is comparatively weak here — a speed-tier coding model, not a frontier reasoner

Open MIT-licensed weights you can self-host

DeepSeek V4

Open weights make this possible at all — Grok Code Fast 1 is API-only, so it cannot leave the vendor's servers.

No long-context surcharge

DeepSeek V4

Its 1M window holds about 3.9× more than Grok Code Fast 1's 256K in a single prompt.

Fast, cheap agentic coding at $0.20/$1.50

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens it undercuts DeepSeek V4 ($0.435/$0.87 per 1M tokens), and that gap compounds at volume.

Low-latency code generation and terminal tasks

Grok Code Fast 1

XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it runs cheaper at $0.2/$1.5 per 1M tokens.

High-volume coding pipelines where speed beats peak quality

Grok Code Fast 1

DeepSeek V4 is comparatively weak here — trails the very best on hardest agentic coding

Lowest cost at scale

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

DeepSeek V4

Its 1M window is about 3.9× larger than Grok Code Fast 1's 256K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens it undercuts DeepSeek V4, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

DeepSeek V4

Larger 1M window fits more in one prompt.

A team with data-privacy or self-hosting needs

DeepSeek V4

Open weights let you run it on your own hardware; Grok Code Fast 1 is API-only.

Anyone whose priority is near-frontier coding at ~1/12 the cost

DeepSeek V4

It is specifically built for that.

Anyone whose priority is fast, cheap agentic coding at $0.20/$1.50

Grok Code Fast 1

That is its strongest area.

An enterprise with regional data-residency rules

Grok Code Fast 1 or DeepSeek V4

Origin (China vs US) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

DeepSeek V4: where it fits

China's open-weight price earthquake — near-frontier capability at roughly a twelfth of GPT-5.5's cost. Released April 24, 2026 by DeepSeek, it is built for near-frontier coding at ~1/12 the cost, open MIT-licensed weights you can self-host, no long-context surcharge, and highest LiveCodeBench result.

Its trade-offs are real: trails the very best on hardest agentic coding, and text/code focused, less multimodal. At $0.435 in / $0.87 out per million tokens, it sits in the budget price band.

Grok Code Fast 1: where it fits

XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. Released August 28, 2025 by xAI, it is built for fast, cheap agentic coding at $0.20/$1.50, low-latency code generation and terminal tasks, high-volume coding pipelines where speed beats peak quality, and a 256K window sized for real codebases.

Its trade-offs: text and code only — no image, audio or video input, xAI did not publish a SWE-Bench Verified score, a speed-tier coding model, not a frontier reasoner, and narrow focus — built for code, not general knowledge work. At $0.2 in / $1.5 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

The defining split here is open vs. closed. DeepSeek V4 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Grok Code Fast 1 gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both DeepSeek V4 and Grok Code Fast 1 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is DeepSeek V4 or Grok Code Fast 1 better for coding?

Public SWE-Bench figures are not available for Grok Code Fast 1, so the honest test is your own repository — run an identical real bug through both. By design, DeepSeek V4 leans toward near-frontier coding at ~1/12 the cost while Grok Code Fast 1 leans toward fast, cheap agentic coding at $0.20/$1.50, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, DeepSeek V4 or Grok Code Fast 1?

DeepSeek V4 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Grok Code Fast 1 is API-metered at $0.2/$1.5 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

DeepSeek V4 — 1M vs 256K, about 3.9× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both DeepSeek V4 and Grok Code Fast 1 together?

Yes — a multi-model platform like LumiChats gives you DeepSeek V4, Grok Code Fast 1 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, DeepSeek V4 or Grok Code Fast 1?

DeepSeek V4 — released April 24, 2026, about 8 months after Grok Code Fast 1.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.