// AI TOOLS · INFLECT-MICRO-V2

Inflect-Micro-v2

An open-source text-to-speech model that packs a complete English text-to-waveform pipeline into roughly 9.4 million parameters — full local speech synthesis in a ~38 MB file that runs on a plain CPU.

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Last verified · 2026-07-26 · by Moe Ameen

What Inflect-Micro-v2 is

Inflect-Micro-v2 is a compact text-to-speech (TTS) model released on Hugging Face by Owen Song, an independent developer, under the permissive Apache-2.0 license. Its whole pitch is size: it packs a complete local text-to-waveform pipeline — the English phoneme frontend, the acoustic model, and the vocoder that produces the actual audio — into about 9.36 million parameters, a roughly 37.5 MB file in FP32. "Full speech capabilities" here means it goes straight from typed English to a finished 24 kHz mono waveform on its own, with no separate vocoder or cloud call in the loop.

Architecturally it sits in the VITS family of end-to-end TTS systems, so the text-to-audio step is a single model rather than a chain of components you have to wire together. It runs on a plain CPU or on CUDA; the model card reports throughput around 6.28× real time on a 4-thread CPU, meaning a minute of speech renders in roughly ten seconds without a GPU. Output is deterministic when you fix the seed, and you get a handful of controls — speaking speed (about 0.5×–2.0×) and a variation dial (0.0–1.0) — plus punctuation-aware segmentation so longer passages stay stable.

Be clear about the scope, because it is deliberately narrow. Inflect-Micro-v2 speaks English only, in a single fixed male voice. It does not do voice cloning, multiple speakers, or other languages — the author frames those as explicit non-goals in service of the tiny footprint. On community blind listening it landed at a 66.2% human-preference rate with a UTMOS22 naturalness score of about 4.4 and a two-ASR semantic word error rate near 4%, which is genuinely strong for a sub-10M-parameter model but still short of large cloud voices. It's the quality-leaning member of the "Inflect v2" pair; a smaller sibling, Inflect-Nano-v2, prioritizes an even smaller footprint under 4M parameters.

Treat the specifics above as a snapshot from the model card and its community discussion, and confirm current numbers on the Hugging Face page before quoting them.

What you can make with it

  • Offline English narration WAV files generated entirely on-device, with no API key, cloud call, or per-character cost
  • Deterministic, seed-locked voiceovers you can regenerate byte-for-byte — useful for testing and reproducible pipelines
  • Scratch narration to audition a script aloud before you commit to a polished voice
  • Accessibility audio (read-aloud text) for apps, docs, and embedded or low-resource devices
  • Batch spoken audio at scale where a fixed English male voice is acceptable and cost matters more than range
  • A drop-in local TTS component for hobby projects, CLIs, and self-hosted tools thanks to the Apache-2.0 license

How Kompozy turns Inflect-Micro-v2 output into content

Inflect-Micro-v2 lives at the very start of the pipeline — the raw "turn this sentence into sound" step — and it does that one thing in a 38 MB file with no cloud dependency. That makes it a great script-audition and scratch-voiceover tool sitting upstream of finished content. The natural workflow: draft your hook and script, run it through Inflect-Micro-v2 locally to hear the pacing and catch clunky lines before you invest in production, tighten the copy, and then bring the finished idea into Kompozy — where the shipping content actually gets made. Kompozy generates the polished spoken voice itself through HeyGen's native TTS on Persona Shorts and Persona HeyGen avatar video, burns in word-synced auto-captions, adds optional B-roll or a VFX hook, and reframes to 9:16, 1:1, and 16:9.

The division of labor is honest: Inflect-Micro-v2 is a free, offline, single-voice narration engine for prototyping and low-cost bulk audio; Kompozy is the generation-and-publishing engine that turns a rough script into a full week of on-brand output — talking-head video, Carousels, Photo Posts, Quote Graphics, a Blog Article, an Email Newsletter, and native Text Posts — all governed by a Persona Brief and fanned across Instagram, TikTok, YouTube, LinkedIn, Facebook, X, Pinterest, and Threads plus blog and email from one queue. Use the little model to pressure-test the words; use Kompozy to ship the finished, captioned, multi-platform content those words become.

  1. Draft your script or hook, then run it through Inflect-Micro-v2 locally to hear how it reads aloud and catch awkward phrasing.
  2. Tighten the copy based on the read, then bring the finished idea or source into Kompozy.
  3. Set a Persona Brief so every generated piece holds your brand voice and banned words.
  4. Generate Persona Shorts or Persona HeyGen avatar video with a real spoken voice and auto-captions, plus Carousels, Photo Posts, a Blog, and a Newsletter from the same idea.
  5. Reframe every asset to 9:16, 1:1, and 16:9 and schedule across eight social platforms plus blog and email with Autopilot and a per-post review pipeline.

Frequently asked questions

What is Inflect-Micro-v2?

It is an open-source (Apache-2.0) text-to-speech model by independent developer Owen Song that fits a complete English text-to-waveform pipeline into about 9.36 million parameters — roughly a 37.5 MB file that runs offline on a CPU and outputs 24 kHz mono audio in a single fixed male voice.

Does Inflect-Micro-v2 support voice cloning or other languages?

No. It is deliberately narrow: English only, one fixed male voice, no voice cloning and no multi-speaker support. The author treats those as non-goals to keep the model under 10M parameters. If you need cloning or many voices, a larger cloud TTS is the right tool.

How good is the quality for such a small model?

Strong for its size but not cloud-grade. Community blind testing put it around a 66.2% human-preference rate with a UTMOS22 naturalness score near 4.4 and a two-ASR word error rate around 4%. Listeners describe it as clearly non-robotic, though inflections can flatten on unfamiliar phrasing.

Can Kompozy import audio from Inflect-Micro-v2?

Kompozy generates its own spoken voice through HeyGen native TTS on avatar-video formats rather than importing external WAV files, so the practical pairing is workflow-based: use Inflect-Micro-v2 to audition and scratch-voice your script locally, then generate the finished, captioned, multi-platform content in Kompozy.

What hardware does Inflect-Micro-v2 need?

Very little. It runs on a plain CPU or on CUDA, and the model card reports about 6.28× real-time throughput on a 4-thread CPU — so a minute of speech renders in roughly ten seconds without a GPU, which is why it suits offline, embedded, and low-resource use.

Related tools

  • Kokoro TTSAn open-weight, 82-million-parameter text-to-speech model that runs high-quality narration locally on a CPU — free, offline, and Apache-2.0 licensed for commercial use.
  • SpeechifyA text-to-speech platform built around low-latency streaming voice — its Simba models turn any script into natural narration for reading, voiceover, and developer apps.
  • HeyGenAI avatar video platform that turns a text script into a talking-head video — in 175+ languages.
  • MetaVoiceA production duplex speech model for revenue phone calls — a single AI that listens and speaks at the same time, so conversations survive interruptions, overlap, and background voices instead of taking rigid turns.

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