Vast.ai
Verified ProviderCommunity Marketplace (Crowdsourced) 4.7 / 5.0 (219 reviews)The Lowest Cost GPU Cloud & Compute Marketplace
Vast.ai connects clients with certified datacenter and host providers in a decentralized marketplace. Consistently offers the absolute cheapest RTX 4090 and 3090 spot pricing worldwide.
Vast.ai GPU Catalog & Real-Time Hourly Pricing (11 Tiers)
| GPU Model (Click for Specs) | VRAM | Interconnect | vCPU / System RAM | Spot Hourly | On-Demand Hourly | Actions |
|---|---|---|---|---|---|---|
| NVIDIA GeForce RTX 3090 | 24 GB | PCIe 4.0 x16 | 4 vCPUs / 16GB | $0.14/hr-36% | $0.22/hr | |
| NVIDIA GeForce RTX 4090 | 24 GB | PCIe 4.0 x16 | 8 vCPUs / 32GB | $0.20/hr-38% | $0.32/hr | |
| 2x NVIDIA GeForce RTX 3090 | 48 GB | PCIe 4.0 x16 | 8 vCPUs / 32GB | $0.28/hr-36% | $0.44/hr | |
| 2x NVIDIA GeForce RTX 4090 | 48 GB | PCIe 4.0 x16 | 16 vCPUs / 64GB | $0.40/hr-38% | $0.64/hr | |
| NVIDIA L40S 48GB | 48 GB | PCIe 4.0 x16 | 12 vCPUs / 64GB | $0.49/hr-29% | $0.69/hr | |
| NVIDIA RTX 6000 Ada 48GB | 48 GB | PCIe 4.0 x16 | 12 vCPUs / 64GB | $0.59/hr-34% | $0.89/hr | |
| NVIDIA A100 SXM4 80GB | 80 GB | NVLink 3 (600 GB/s) | 16 vCPUs / 128GB | $0.85/hr-26% | $1.15/hr | |
| 4x NVIDIA GeForce RTX 4090 | 96 GB | PCIe 4.0 x16 | 32 vCPUs / 128GB | $0.80/hr-38% | $1.28/hr | |
| NVIDIA H100 SXM5 80GB | 80 GB | NVLink (Fast) | 16 vCPUs / 120GB | $1.49/hr-29% | $2.10/hr | |
| 8x NVIDIA GeForce RTX 4090 | 192 GB | PCIe 4.0 x16 | 64 vCPUs / 256GB | $1.60/hr-38% | $2.56/hr | |
| 8x NVIDIA H100 SXM5 80GB | 640 GB | NVLink (Fast) | 128 vCPUs / 960GB | $11.92/hr-29% | $16.80/hr |
Vast.ai Monthly Cost & Stopped Storage Estimator
Simulate your real-world monthly bill including active GPU compute and stopped persistent volume storage overhead.
When you click Stop Instance on Vast.ai, your GPU compute charge stops, but the 200GB disk volume continues billing 24/7 ($20.00/mo) until you terminate the volume. Always backup checkpoints to HuggingFace or S3 before terminating.
Hourly run-rate: $0.20/hr compute + $0.0274/hr disk
Equivalent cloud capacity on AWS would cost approx. $245/mo for 6h daily runtime.
- •Host reliability varies wildly: always filter by 'Host Reliability > 98%' and 'Direct Port Mapping' to avoid unstable rigs.
- •Spot instances (Interruptible) can be outbid and reclaimed instantly without graceful checkpoint buffers if price spikes.
- •Some consumer 4090 host boards lack proper PCIe lane bifurcation (running at x4/x8 instead of x16), slowing model weight loading.
- ✓Use the Vast CLI `vastai search offers 'reliability > 0.98 inet_up > 200 cuda_vers >= 12.2'` for high-confidence picks.
- ✓Check host motherboard topology with `nvidia-smi topo -m` immediately after launch to confirm PCIe/P2P link speeds.
- ✓Mount remote S3/B2 buckets using `rclone` with caching rather than storing heavy checkpoints on unverified host disks.
Full-Lifecycle TCO & Hidden Cost EstimatorReal Invoicing
Calculate actual project costs including stopped storage fees and network egress penalties.
Top Alternatives to Vast.ai
Evaluate competing GPU clouds for pricing, speed, and platform reliability.
The developer cloud with 1-click pods & persistent network storage
RunPod guarantees enterprise Tier 3 datacenters with ISO certification, standardized 10 Gbps HuggingFace cache mounts, and official 1-click ComfyUI Docker pods with zero host eviction.
Low-cost bare metal cloud with custom vCPU/RAM allocation
TensorDock provides dedicated enterprise colocation with root SSH, zero mandatory KYC, and cryptocurrency (USDT) billing, without peer-to-peer security concerns.
Curated AI cloud with pristine NVIDIA stack & NVLink clusters
Lambda Stack comes pre-configured with PyTorch, CUDA, and cuDNN without dependency hell. Top choice for SXM5 H100 clusters when multi-GPU NVLink is non-negotiable.
Ultra-fast InfiniBand AI cloud for 70B+ LLM training
Delivers true 3.2 Tbps InfiniBand cluster fabric with Slurm scheduling, ideal for multi-node DeepSeek and Llama 3 training that exceeds PCIe bandwidth limits.
In-Depth Technical Head-to-Head Battles:
Comparing RunPod vs Vast.ai pricing: Choose RunPod for 1-click Docker templates (ComfyUI/vLLM), reliable Tier 3 datacenters, and zero-headache network volumes. Choose Vast.ai for raw compute affordability and the cheapest RTX 4090 spot pricing in the world ($0.20/hr).
Searching for Lambda Labs alternatives due to frequent 'Out of Capacity' errors? RunPod Secure Cloud and Vast.ai are the two premier alternatives, delivering instant availability for RTX 4090, A100 80GB, and H100 SXM5 instances with root SSH and high-speed network volumes.
For ComfyUI image and video generation (FLUX.1-dev, SDXL, Wan2.1), 24GB VRAM on NVIDIA RTX 4090 is the gold standard. RunPod offers pre-configured ComfyUI pods with custom nodes and persistent storage. Vast.ai offers unbeatable spot pricing for budget batch generation.
SaladCloud is the cheapest platform in the world ($0.08/hr for RTX 3090, $0.14/hr for RTX 4090) for headless, asynchronous batch workloads like Whisper audio transcription and dataset diffusion rendering. Vast.ai is the superior choice for interactive development, persistent storage, direct root SSH terminal access, and custom multi-GPU rigs.
1-Click Docker & SSH Recipes for Vast.ai
Tested terminal commands for immediate deployment on NVIDIA GeForce RTX 3090 instances.
# 1. SSH into your Vast.ai instance: # ssh root@<instance_ip> -p <ssh_port> # 2. Launch ComfyUI with FLUX.1 & SDXL model cache: docker run -d --gpus all --name comfyui \ --restart unless-stopped \ -p 8188:8188 \ -v /workspace/ComfyUI/models:/root/ComfyUI/models \ -v /workspace/ComfyUI/output:/root/ComfyUI/output \ yanwk/comfyui-boot:cu124 # Access ComfyUI in your browser at: http://<instance_ip>:8188
Vast.ai Architecture, Gotchas & Engineering Verdict
Vast.ai operates as a decentralized compute marketplace. Hardware is hosted by verified data centers and independent node operators globally, yielding dramatic cost savings on spot capacity.
- ✓Extremely competitive hourly spot rates with up to 60% savings.
- ✓Direct root SSH and Docker container flexibility.
- ✓USDT / Crypto payment supported with zero KYC.
- !Stopped Storage Fee: Persistent disk volumes accrue billing 24/7 ($0.02 - $0.05/GB/month) until deleted.
- !Preemption Risk: Spot instances can be interrupted if a higher bidder arrives. Write frequent model checkpoints.
- !Bandwidth Variance: Verify host download speeds before pulling 50GB+ model checkpoints.
Developer Reviews & Telemetry Audit
Aggregated from 219 verified AI engineers deploying vLLM, ComfyUI, and production API workloads.
“You simply cannot beat $0.20/hr for an RTX 4090. As long as you write resilient checkpointing to Cloudflare R2 to handle occasional spot host interruptions, Vast.ai is the highest ROI platform on earth.”
“Renting 3090 instances at $0.14/hr let me bootstrap my SaaS for under $100/mo. Just use the filter to pick hosts with high bandwidth scores.”