VerbaClara 0.9.0 Chrome · Edge · Brave For people who write in a second language

Fix the words. Learn the why.

Select a sentence in most places you write. VerbaClara fixes it, explains the rule in the language you think in — offline for common mistakes — and turns the mistakes you keep making into practice. Harper runs on your computer by default.

Get VerbaClara Free Play with the demo

Free with Harper, Ollama, or your own key No account No VerbaClara servers

mail.northwind.co/compose VerbaClara on

New message

Draft saved
Toteam@northwind.co
SubjectQ3 report follow-up

Hi team, I am writing to follow up on the report. I have went1 through the numbers and I think we should discuss about2 the timeline.

Live demo — this is the real panel, rebuilt for the page. Change the language, switch the tone, or apply the fix. Nothing is sent to VerbaClara. Model mode shown. In the extension, the first explanation works offline in seven languages; the chips here are a demo control.

01 How it works

Select. Fix.
Understand.

The loop is small on purpose. It fits between two thoughts — not in another tab, not in a twelve-step grammar course.

01Anywhere you write

Select what you wrote

Highlight a sentence in an email, a form, a post or a chat. A small VerbaClara button appears. Right-click works too — or let Auto mode check when you pause.

02Four voices

Pick a voice

Keep it simple with Fix, or shift the register with Formal, Casual or Shorter. Meanings stay yours.

03The part that stays

Read the why

The rule arrives in the language you chose, in plain words. One tap files the mistake for practice.

Works in normal text fields and many rich editors. Google Docs is the honest exception — see coverage.

02 The part everyone skips

A correction is easy to accept.
A rule is harder to forget.

Most tools stop at the green check. VerbaClara is built for the moment after it.

You don’t need this sentence fixed. You need the rule that fixes the next one.

VerbaClara keeps the thing you actually wrote: the wrong phrase, the fix, the rule. It names the pattern, explains it in your language, and hands it to the Practice Lab. The next time it shows up in your inbox, you recognise it.

Your language
Written like a teacher sitting next to you — not like a grammar dictionary.
Your pattern
Clusters come from your own crumbs, not a generic course.
Your machine
Harper runs on-device. History stays in chrome.storage.local.

Honest bit: the first explanation is built offline for common grammar categories. Deeper, context-specific explanations need a model. Harper, the default, gives you on-device grammar and the offline first explanation.

Draft · email to team Mon 09:41

Hi team, I am writing to follow up on the report. I have went through the numbers and I think we should discuss about the timeline.

ES

En el presente perfecto, después de have va el participio: gone, no went.

DE

Discuss heißt „besprechen“. About ist überflüssig.

Two corrections. Two rules. Both are saved for practice.

03 Practice Lab

Your mistakes become
the curriculum.

Not a generic grammar course. The Lab clusters the crumbs from your own writing, then quizzes the pattern until it moves from New to Mastered. No history yet? Four foundational clusters get you started.

VerbaClara 0.9.0

Detected weakness clusters

Built from crumbs. Never full emails.

Prepositions 0 of 4 answered this session

We will meet ___ Monday morning.

Pick one. The Lab records mastery after you answer.

Mastery · Learning
9 mistake categories 0–3 mastery levels Sample Lab shown. Yours is built in your browser.

04 Choose the brain

Harper by default.
Your model when you want more.

One setting decides where your sentence goes. Start fully on your computer. Add a model only for tone, translation and lessons.

Runs on this computer

No model to install. Nothing to send.

Harper is a grammar engine compiled to WebAssembly inside the extension. It checks English spelling and grammar, applies its own suggestions, and files the fixes it applies into one of nine learning categories. Fix mode only.

  • English grammar & spelling
  • No network, no key, no setup
  • Offline explanations in seven languages
What it won’t do: rewrite tone or explain deeper context. Offline templates cover common categories; a model adds nuance.
This page→ VerbaClara→ Harper · WASM
wasm · local · no request offline
VerbaClara serverdoes not exist
Also works with these supported OpenAI-compatible servers
GroqDeepSeekMistralOpenRouterMiniMaxLM Studio

05 Privacy

No VerbaClara servers.
Nothing to sell.

The free tier has no backend and no account. For fixes, your sentence goes to Harper on your computer, to a model on your localhost, or to the provider whose key you pasted. Practice Lab sends only short crumbs to the lesson model you choose. That is the whole map.

What a cloud fix call looks like masking on

Hi Priya, send the signed copy to [EMAIL] or call [PHONE]. The brief is at [URL] — ref [NUMBER].

localhost:11434 api.openai.com Google Gemini

For fix and rewrite requests, emails, phone numbers, URLs and long digit strings become placeholders before the call, then are restored. Practice Lab uses a separate lesson model and sends only short crumbs. Names and context are not masked.

01

No backend to leak

There is no VerbaClara account, no sync and no analytics SDK. The extension ships with network access only for localhost and the AI provider domains in its manifest.

02

Crumbs, not emails

History stores the wrong phrase, the correction, the rule label and the category — capped at 500 entries in chrome.storage.local. Each side is limited to 80 characters; full messages and documents are never saved.

03

One switch to stay local

Local-only mode blocks every non-localhost endpoint, including a cloud lesson model. Harper and a local Ollama model already keep fix text on your machine; the switch closes the rest.

Read the full privacy policy No cookies on this page. No analytics. No VerbaClara servers.

06 Honest coverage

We’d rather tell you
where Replace fails.

Some editors accept inserted text. Some intercept it. A few block it entirely. Where the Fix UI runs, VerbaClara offers Copy when Replace fails — and tells you before you find out mid-email.

Replace in place

Plain inputsTextareasRedditMany forms

The clean path: the corrected sentence goes straight back into the field where you wrote it.

Copy is the path

GmailSlackOutlook webNotionChat UIs

These editors often intercept programmatic edits. VerbaClara hands you the corrected text and a one-key copy instead of pretending.

Not in place

Google DocsCross-origin iframes

Docs blocks selection tools; cross-origin iframes never receive the injected UI. On Docs you get a clear message and Copy when the editor permits it. In an iframe, use the browser’s own copy/paste — the extension cannot reach it.

Copy is the fallback. We’d rather hand you the sentence — and admit when a page blocks that too — than claim a guarantee the page can’t keep.

07 Price

Free where
learning happens.

The whole coaching loop is free with Ollama or your own key. Hosted AI is planned for people who want zero setup — never as a gate on lessons.

Free · bring your own AIStart here
$0 forever

The core works offline. Add Ollama or your own key for deeper explanations, tone rewrites and Lab lessons.

  • All four modes — Harper for Fix, a model for tone
  • Offline explanations in seven languages, plus deeper context with your model
  • Practice Lab, weakness clusters, mastery
  • Harper on-device + Ollama, OpenAI, Gemini, supported compatible servers
  • No account, no VerbaClara servers
Download VerbaClara

No card. No trial. No “free plan” asterisk.

Not for sale yet
Pro · hosted AILater
TBD

For people who want zero setup: we run the model. The learning features stay free.

  • No Ollama, no API key, no configuration
  • Same fixes, tones, Lab and history
  • Practice Lab is not behind this plan
  • Ships only after the Chrome Web Store listing has real reviews

Price announced when it ships. No lifetime deal, no launch discount.

Gate Store reviews first, then hosted AI. Learning stays free.

08 Install

Two minutes.
No account.

The Chrome Web Store listing is next, not live. Until it is, the unpacked build below is the real extension — same code, version 0.9.0.

Unpacked install · Chrome, Edge, Brave

  1. Download the zip and unzip it.
  2. Open chrome://extensions and turn on Developer mode.
  3. Click Load unpacked and choose the unzipped folder. Pin VerbaClara.
  4. Open Settings: the first explanation is offline. A model is optional for deeper context.

The Store build will come from this same source. When the listing goes live, this page will switch to the one-click link.

VerbaClara 0.9.0

Download .zip

8.5 MB · Manifest V3
Chrome, Edge, Brave

AltA apply AltG grammar AltI ignore

09 FAQ

Questions,
answered.

The honest ones first. If something is missing, the privacy policy and the build are both linked at the bottom.

Is VerbaClara another Grammarly?

No. Grammarly corrects. VerbaClara corrects and then teaches: the rule in your language, and practice built from your own mistakes. It also isn’t a subscription: the core is free, and local Ollama or your own key unlocks deeper explanations without a VerbaClara server.

Do I need an API key?

Not to start. Harper runs inside the extension on your computer — no key, account or card. The first explanation of common grammar mistakes is built offline in your language. For deeper explanations, tone rewrites and Practice Lab lessons, choose a local Ollama model or paste your own OpenAI or Google key.

Which model should I use?

Start with Harper for English grammar and the offline explanations. A model adds context-specific explanations in Spanish, German, Japanese or another language. Locally, llama3.1 is a good default and qwen2.5:7b is stronger for multilingual work. The build also supports the OpenAI-compatible servers listed in the engines section.

What actually leaves my computer?

With Harper or Ollama, a fix or rewrite stays on your computer. With a cloud key, the selected sentence goes to the endpoint you configured after emails, phone numbers, URLs and long numbers are masked.

Practice Lab is separate: it uses the lesson model you choose — local, OpenAI or Google — and sends only short wrong → correct crumbs, never the original email. Masking covers fix and rewrite requests; lesson crumbs are short but not PII-masked. Names and context are not masked on either path, so use Ollama or Local-only if that matters.

Does Replace work on Gmail, Slack or Google Docs?

Gmail and Slack often intercept in-place edits, so VerbaClara uses the Copy fallback there. Google Docs blocks selection tools almost entirely, and cross-origin iframes never get the injected UI. The coverage section is the honest map; Copy works wherever the editor permits it.

Can it check languages other than English?

Harper is English-only. The offline explanation pack covers common categories in seven languages; a model can check other target languages and explain deeper context. The interface is English. Set “I write in” and “Explain my mistakes in” separately in Settings.

Is my API key safe?

It is stored in chrome.storage.local on your device and sent only to the endpoint you configured. No VerbaClara server ever sees it. For the strongest guarantee, use Ollama or turn on Local-only mode, which blocks every non-localhost endpoint.

When is the Chrome Web Store version out?

Submission is the next step; right now you can install the unpacked build from the zip above. It is the same code. Hosted Pro ships only after the listing has real reviews — not before.

Will there be a Firefox version?

It is on the roadmap after Chrome. VerbaClara is Manifest V3 today, so Firefox is a port — not a promise with a date attached.