Quick answer
How do you make AI-generated text sound human?
Rebuild the statistical signals models flatten: vary sentence length (burstiness), replace stock phrasing like 'in today's landscape' or 'leverage', break repeated sentence openers and passive voice, and add real specifics. PostSpark does this in three passes — analyse, rewrite, repair — then verifies your numbers, names and links are still intact and shows the before/after score for each signal. Free for 3 runs per month.
Make AI text read like you actually wrote it.
Paste ChatGPT, Claude or Gemini output. PostSpark analyses it, rewrites it in your Brand Voice, then re-reads its own draft to check your facts survived — and shows you every number behind the change.
- 3 free repurposes monthly
- No credit card required
- Cancel anytime
Input
Output — in your voice
● LiveTrusted by 2,400+ creators & agencies shipping daily
The problem · The fix
What's costing you hours — and how PostSpark removes it.
What's draining your week
- Raw AI copy reads mechanical — readers bounce on the first line.
- Other humanizers swap synonyms, mangle your numbers, and promise '100% undetectable'.
- You get one block of text back with no way to fix the sentences you dislike.
What PostSpark gives you
- Three passes: analyse the tells, rewrite against them, repair anything that drifted.
- Per-sentence accept, revert or re-roll — the final copy is assembled from your choices.
- Your trained Brand Voice and Brand Kit tone feed the rewrite, so it stays yours.
Your workflow
How it works for you
Paste or import your draft
Up to 20,000 words, or pull it straight from Google Drive.
Set intensity and purpose
Light, medium or strong — plus purpose, style and anything to preserve.
Review the diff, then publish
Score breakdown, meaning check, sentence controls, and full run history.
Scored live in your browser
Same message. Two very different reads.
These scores are computed right now, on this page, by the exact model the PostSpark editor uses. Nothing here is a screenshot.
After PostSpark
I posted every weekday for 90 days. Nothing happened for the first six weeks. Then one post did 140,000 views. Same topic I'd been writing about since day one, same opinions, same account. Here's what changed: I stopped explaining what I do and started showing what I'd figured out that week. Specific numbers. Things that went wrong. Personal brand isn't a strategy deck. It's just being the person who keeps showing up with something real to say.
Raw AI draft
53% estimated AI likelihood
After PostSpark
24% estimated AI likelihood
PostSpark's own estimate from measurable text signals. It is not a verdict from any third-party detector, and no tool can promise one.
How detection actually works
Six signals, measured every run
Detectors don't read for meaning. They look for statistical regularity. So that's what we measure, show you, and rewrite against.
- Burstiness
- Human writing swings between 4-word lines and 25-word lines. Models hold a steady 15 to 20. We measure the spread and rebuild it.
- Word predictability
- Models pick the statistically likeliest next word. We track lexical variety and repeated phrasing, then push the rewrite toward less predictable, more specific wording.
- Stock phrasing
- A library of 120+ tells: “in today’s landscape”, “it’s important to note”, utilize, leverage, seamless, tapestry, “not only… but also”, em-dash pivots.
- Rhythm & structure
- Repeated sentence openers, passive voice, uniform paragraph shape, and a topic-sentence announcement at the head of every paragraph.
- Readability
- Thesaurus-soup output beats detectors and loses readers. We hold Flesch reading ease inside a human band instead of maximising complexity.
- Meaning integrity
- Numbers, percentages, dates, names and URLs are extracted from your source and verified present in the output. Nothing quietly drifts.
Honest comparison
Why this isn't another spinner
Rewrite your next draft in your own voice
Three passes, a full signal breakdown, sentence-level control and a meaning check on every run. 3 free runs every month, no credit card.
Humanize my first draft freeHumanizer questions
Before you paste a draft
How does PostSpark humanize AI text?
It runs three passes. First it analyses your text and reports exactly which machine-writing tells it found. Then it rewrites with those findings plus your purpose, style and Brand Voice. Finally it re-reads its own draft, checks your facts and numbers are intact, and repairs only the sentences that still read mechanical.
Will it get past AI detectors like GPTZero or Originality.ai?
We do not promise that, and any tool that guarantees it is not being straight with you. Detectors change weekly and none of them publish their model. What PostSpark does is measurably reduce the statistical signals detectors look for, then show you the numbers so you can decide whether to publish.
What is the score on the results screen?
It is PostSpark's own estimate, not a detector verdict. We measure burstiness (sentence-length variation), word predictability, stock AI phrasing, rhythm and passive voice, readability, and human voice cues like contractions. Every signal is shown separately with its before and after value, and the estimate is labelled as an estimate everywhere it appears.
Does it change my facts, numbers or names?
It is instructed not to, and we verify it. After every run we extract the numbers, percentages, dates, names and links from your source and check each one is still present in the output. If anything is missing, a repair pass restores it and the results screen flags what changed.
Can I edit the rewrite sentence by sentence?
Yes. The Diff view shows every sentence that changed next to your original. You can accept it, revert to your wording, or re-roll that single sentence in context as many times as you want. The final text rebuilds from your choices, so you own the copy.
How long can the text be?
Up to 20,000 words. Anything over roughly 1,200 words is split on paragraph boundaries and humanized section by section, with the output streaming in as each section finishes. Long-form batch mode is a Pro feature and one document counts as one run, not one per section.
Does it write in my voice or a generic one?
In yours, if you have trained a Brand Voice. Pro plans feed your voice profile and active Brand Kit tone into the rewrite pass, so the output keeps your vocabulary and register instead of drifting into generic blog voice.
What does it cost?
The free plan includes 3 runs per month with no credit card. Pro is $24/mo ($19/mo billed annually) for unlimited runs, long-form batch mode, Brand Voice and full run history.
Simple pricing. Real value.
Start free forever. Upgrade whenever you're ready to ship a month of content in an afternoon.
Switch to annual for two months free.
Free
Try it without a credit card.
- 3 repurposes per month
- All content formats
- Tweet, LinkedIn & email outputs
- Copy and export
- Brand Voice AI
- Unlimited repurposes
Pro
For creators who publish daily.
- Unlimited repurposes
- All content formats
- Brand Voice AI training
- Spark Copilot assistant
- AI Image Studio
- Hook Lab + virality scoring
- SEO Blog Writer
- Content Calendar
- Priority generation
- History & regeneration
30-day money-back guarantee
Agency
For teams and agencies.
- Everything in Pro
- 5 team seats
- Multi-brand workspaces
- Client approval links
- White-label review pages
- Agency analytics rollup
PostSpark replaces: Jasper ($49) + Buffer ($15) + Canva Pro ($15) + Surfer SEO ($89) = $168/month
PostSpark Pro: $19/month billed annually.
FAQ