True offline speech recognition means the audio never leaves your device. The model loads locally, runs on your CPU or GPU, and produces text in the same process — no network roundtrip, no upload, no cloud dependency. In 2026 there are five consumer dictation apps that meet this definition cleanly: SnailText, MacWhisper, SuperWhisper (local mode), Voibe, and VoiceInk.
This comparison covers all five. The criteria: privacy architecture (what actually leaves the device), platform support, GPU acceleration, accuracy, and price.
Disclosure: SnailText is our own product. We’ve tried to rank these honestly and tell you exactly when a competitor is the better buy — the per-app picks below name MacWhisper, SuperWhisper, Voibe, and VoiceInk as the right choice for specific cases. Run the network-capture test at the end on any app, including ours, and verify the privacy claims yourself.
The privacy architecture check nobody else does
Before ranking on features, the most important question is: what actually leaves your machine during a dictation?
“Offline” and “local” are used loosely. One app in this category deserves scrutiny:
SuperWhisper runs STT locally — the audio is transcribed on your device. But the Smart Modes feature, enabled by default, makes outbound cloud requests during dictation. In our network capture (June 2026), those requests carried context such as the active application name, the focused text-field content, and clipboard data. The STT is local; the context enrichment is not. Run the network-capture test below to confirm the current behavior for yourself before relying on this.
SnailText sends nothing during dictation. Audio stays in RAM and is discarded after transcription. The optional Pro AI correction (Gemma) runs locally too — no API key, no cloud LLM call.
This distinction matters most for healthcare, legal, and enterprise use cases. For everyone else, it is worth knowing what you are actually getting.
Five apps compared
| Feature | SnailText | MacWhisper | SuperWhisper | Voibe | VoiceInk |
|---|---|---|---|---|---|
| Platforms | ✓ Mac + Windows | Mac only | Mac + Windows | Mac only | Mac only |
| Windows GPU | ✓ Vulkan | — | CPU only | — | — |
| Mac GPU | ✓ Metal | ✓ Metal | ✓ Metal | ✓ Metal | ✓ Metal |
| Free tier | ✓ Unlimited | ✓ Tiny + Base | 15 min (cloud) | No | Free (build) |
| Price | Free / $7.49/mo | Free / $49 | $8.49/mo | $198 lifetime | Free / $4.99/mo |
| Fully local? | ✓ Nothing uploaded | ✓ Yes | STT yes, context no | ✓ Yes | ✓ Yes |
| Local AI LLM | ✓ Gemma on-device | — | Cloud only | — | — |
| Vocabulary / custom dict | ✓ Pro | — | ✓ Yes | — | — |
Competitor prices and platform details verified June 2026 — check each vendor’s site for current figures.
The apps, one by one
SnailText — our own product. Mac (Apple Silicon) and Windows, with GPU acceleration on both (Metal on Mac, Vulkan on Windows — no CUDA required). Audio is held in RAM and discarded the moment transcription finishes; there is no upload path to disable because none exists. The free tier runs Whisper Tiny and Base with no word limit and no account. Pro ($7.49/mo) adds larger models and a local Gemma correction step that also runs on-device. The main gap: no mobile apps and no file-transcription workflow — it is built for live dictation into whatever app has focus.
MacWhisper — Mac-only, and the strongest option in this list for transcribing existing audio files (meetings, interviews, podcasts) rather than live dictation. Built on whisper.cpp with Metal acceleration. The free tier covers Tiny and Base; the $49 one-time license is the best value in the category if file transcription is your main job. No Windows build and no live-dictation vocabulary injection.
SuperWhisper — Mac and Windows, with the most complete Modes system (per-context model, vocabulary, and prompt). STT runs locally, but the default Smart Modes feature sends context — app name, focused text-field content, clipboard — to the cloud, so it is not fully offline out of the box. The Windows build has no GPU acceleration as of June 2026, which shows up as long post-stop latency on larger files. Pick it if you are Mac-primary and want the deepest configurability and accept the Smart Modes trade-off.
Voibe — Mac-only, deliberately simple and fast, with Metal acceleration and lifetime pricing ($198). Fully local — nothing uploaded. There is no free tier, so you commit up front, but at 18+ months of daily use it works out cheaper than a subscription. Choose it if you want a no-frills local dictation app on Mac and prefer to pay once.
VoiceInk — Mac-only, open-source (GPL v3), built on whisper.cpp. Free if you build it from source. Fully local with no uploads. The cost is your time: there is no signed installer or polished onboarding, so it suits technical users comfortable compiling a Swift/whisper.cpp project. No Windows build.
Accuracy: what the numbers actually mean
All five apps use Whisper under the hood (VoiceInk via whisper.cpp, SnailText via whisper-rs, MacWhisper via the same). SuperWhisper and SnailText also offer Parakeet TDT v3 for English-primary use cases.
On the LibriSpeech clean-speech English benchmark, Whisper Large-v3 achieves approximately 2.7% Word Error Rate — competitive with cloud APIs at their best. Whisper Base achieves approximately 5–6% WER. The difference is model size, not cloud vs local.
In practice:
- Clean English in a quiet room: all five apps produce comparable results with the same model size. The difference is negligible.
- Accented or fast speech: Whisper Medium and above handle accents well. If you are a non-native English speaker, test with at least Small.
- Technical vocabulary: SnailText and SuperWhisper both support vocabulary lists. MacWhisper does not have live dictation vocabulary injection.
- Noisy environments: VAD quality matters more than model accuracy here. SnailText and SuperWhisper use Silero VAD.
GPU acceleration: what it changes
GPU reduces post-stop latency — the time between stopping a recording and text appearing. On CPU alone, Whisper Base takes 1–3 seconds for a 10-second phrase. On GPU, under 300ms.
SuperWhisper’s Windows build does not have GPU acceleration as of June 2026 — latency was 29 seconds for a 3.5-minute file in our test. SnailText uses Vulkan on Windows, which works on NVIDIA, AMD, and Intel Arc GPUs without requiring CUDA.
When to pick which app
Pick SnailText if: you need Mac and Windows with the same experience, want GPU acceleration on both platforms, or need an unlimited free tier. The Pro tier adds larger models and local Gemma AI correction.
Pick MacWhisper if: you are Mac-only and primarily transcribing files — meetings, interviews, recordings. The $49 lifetime price is the best value for file transcription specifically.
Pick SuperWhisper if: you are Mac-primary and want the most feature-complete Modes system — per-context model, vocabulary, and prompt. Understand that Smart Modes sends context to cloud by default.
Pick Voibe if: you want a simple, fast Mac dictation app with lifetime pricing. Works out cheaper than subscriptions at 18+ months of use.
Pick VoiceInk if: you are technical, on Mac, and want zero cost. GPL v3, build it yourself, no subscription needed.
The one thing most comparisons miss
The test that separates truly offline apps from “mostly offline” ones is a network capture during an active dictation. Open Little Snitch on Mac or GlassWire on Windows, start recording, and watch the outbound traffic column.
A truly offline app produces zero outbound requests during recording and transcription. You may see requests at launch (update check) or after (license verification), but nothing during the actual audio-to-text conversion. That is the test — not policy documents.
Of the five apps here, four pass cleanly: SnailText, MacWhisper, Voibe, and VoiceInk. SuperWhisper passes on STT but fails on context enrichment when Smart Modes is active.
Run the test before you commit. It takes 60 seconds and tells you more than any privacy page.