Your AI coworker, built into the doc.

Write with AI — not around it.

Stop copy-pasting between ChatGPT and your documents. SidePen brings AI directly into a clean, distraction-free editor — so you can collaborate in real-time with an AI coworker who's already read everything.

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The quarterly report needs to cover three main areas: revenue growth, customer acquisition, and product updates.

AI continuing... Let me expand on each section with specific metrics and highlights from Q4...

Brainstorm before you write

Not sure where to start? Our brainstorm flow asks the right questions to understand your vision, then creates a tailored first draft — so you never face a blank page alone.

The old way is broken.

You know the drill. Open ChatGPT. Copy your paragraph. Paste it. Ask for a rewrite. Copy the result. Paste it back. Realize it lost your voice. Try again.

“Please fix the third paragraph but keep the second one intact and match the tone of the first.”

Context is lost. Flow is broken. Writing becomes a chore.

AI that works with you, not beside you.

SidePen embeds AI directly into your writing. No tabs. No copy-paste. No explaining what you meant.

Your AI coworker sees what you see. Highlight a sentence and ask for a rewrite. Hit a wall and let it continue your thought. Type a slash command and watch your outline expand into prose.

It's the way AI writing should have always worked.

Finally, an editor that respects your focus.

Most writing tools are cluttered with menus, panels, and options you'll never use. SidePen strips it all away. What's left is a calm space for your words — and an AI assistant that appears only when you need it.

No toolbar hunting. No settings rabbit holes. Just you, your thoughts, and the gentle presence of an AI coworker ready to help when you ask.

Read Aloud

Hear your writing spoken back to you. Catch awkward phrasing, clunky rhythm, and sentences that trip over themselves — before your readers do.

Let me read that back to you! Sometimes a sentence looks perfect on screen but stumbles when it's spoken. I'll say your words out loud so you can hear what your reader will feel — the rhythm, the pauses, the parts that sing and the parts that snag. If it rolls off my tongue, it'll roll off theirs.

Why writers love SidePen

Stay in Flow

Context-switching kills creativity. When AI lives in your document, you keep writing — no tabs, no paste, no friction. The UI disappears until you need it.

Write Faster

Start with a thought. Let AI help you expand, refine, and polish — all without leaving your editor.

No More Blank Pages

Stuck? Your AI coworker is right there with suggestions, continuations, and ideas that match what you've already written.

Calm by Design

No clutter. No distractions. The UI fades away so you can focus on what matters: the words on the page.

How it works

1

Just start writing

Open a calm, minimal editor. No menus to navigate, no settings to configure. Start typing — the interface disappears and it's just you and your words.

2

Collaborate inline

Highlight text to rewrite it. Use slash commands to expand, summarize, or transform. Get suggestions that continue your thought.

3

Finish faster

No copy-paste loops. No lost context. Just you and your AI coworker, finishing what you started.

The Old Way

  • ×Open AI chat in another tab
  • ×Copy your text, paste it, explain what you need
  • ×Copy the result, paste it back
  • ×Realize it missed the point
  • ×Repeat until frustrated

The SidePen Way

  • Highlight → Rewrite
  • Slash command → Expand
  • Stuck → AI continues your thought
  • Done.

Start writing with your AI coworker.

Free to use. No credit card. No copy-paste.

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