The verdict
Hammer AI's homepage claim — '100% free and completely private character roleplay' — is accurate. The platform covers two distinct creative modes: Characters (persistent companion roleplay with memory) and Stories (collaborative narrative writing), both available under the same free plan. Desktop apps exist for Windows, Mac and Linux; iOS and Android mobile apps are also listed in the live site navigation — making it the rare local-AI tool with genuine native mobile support. The privacy guarantee is genuine on the local path: running models through Ollama means your conversations stay entirely on your machine, with no data sent to Hammer AI's servers. Free users also receive a daily cloud message quota for trying cloud-hosted models without committing to a plan. Lorebooks, group chat (multiple characters simultaneously), TTS voice output and integrated image generation are all included on the free tier — no paywall separating these features from paying users. The honest constraint is hardware: local models via Ollama need a capable GPU (7B models require 8 GB+ VRAM at minimum). Without one, users depend on the metered free cloud quota, which runs out during heavy sessions. Users wanting deeper model customization or a wider model library than Hammer AI bundles will still prefer SillyTavern — but Hammer AI's combined free + private + mobile + beginner-friendly package has few direct rivals.
Free, private, multi-platform local chat. For deeper model customization, SillyTavern; for polished cloud inference with GPU pricing, Backyard AI.
Pros
- Genuinely 100% free with no usage limit on local models
- Two modes: Characters (companion) and Stories (narrative writing)
- Desktop (Win/Mac/Linux) and mobile (iOS/Android) native apps
Cons
- Local performance needs capable GPU (8 GB+ VRAM for 7B models)
- Cloud free quota runs low in heavy sessions
- Less model variety and customization than SillyTavern
Hammer AI FAQ
Does Hammer AI need a GPU to run locally? Yes for local models — 7B models need roughly 8 GB VRAM. Without a compatible GPU, you can use the free daily cloud quota or a paid cloud tier, which works on any device.
What is the difference between Characters and Stories mode? Characters mode is persistent companion roleplay with memory — you build a relationship over time. Stories mode is collaborative narrative writing, more like co-authoring fiction than chatting with a companion.
Does Hammer AI have a mobile app? Yes. iOS and Android apps are available alongside the desktop applications for Windows, Mac and Linux.
Is Hammer AI really completely free? Local use via Ollama is fully free with no usage limit or paywall. Paid cloud tiers (Starter ~$9/mo, Advanced ~$18/mo, Ultimate ~$35/mo) add cloud LLMs, context window size and image/voice credits for users without a GPU.
How private is the local mode? With Ollama running locally, your prompts and responses never leave your machine — Hammer AI has no access to local-mode conversation content. Cloud mode sends prompts to their server, so the full privacy guarantee only applies when running locally.
Scored on the public six-point method, assessed against documented features, pricing and real user reports (plus hands-on use where we have account access) · last updated September 2026.