AI Quality Tiers

Every AI-powered tool in Diglot — translator, paraphraser, grammar checker, AI detection, Co-writer, and templates — runs at a quality level we call a tier. Higher tiers produce more natural, polished English, which matters most when you’re writing toward a native-speaker standard.

There are three quality tiers, and your plan sets which one you get by default.

The three tiers

Tier	Plan	What it’s good for
⚡ Fluent	Free	Fast and capable for everyday writing — drafts, quick rewrites, and basic grammar.
✦ Smart	Spark ($19/mo)	Higher quality for nuanced edits — better tone awareness and more natural phrasing.
🎯 Native	Pro ($29/mo)	Top quality for publication-level English — academic papers, professional documents, and final polish.

The tier names describe the quality of the writing, not the technology behind it. “Native” means the result reads as if a native English speaker wrote it — that’s the bar.

Max plan uses the same top Native quality as Pro. What Max adds is far more capacity (20× Pro’s monthly limits), maximum reasoning effort, and the deepest assistant memory — so it’s the best quality plus the most room to work, rather than a new quality level.

How your assistant remembers your work

The Co-writer keeps memories across your sessions. Every plan has memory turned on, but how much it remembers depends on your plan:

Plan	What it remembers
Free / Spark	Durable “Memories” — facts you save or confirm
Pro / Max	Full cross-session recall — a broader, automatic memory of your past work

Switching tiers as you write

There’s a small quality switcher in the editor header — a pill-shaped dropdown showing your current tier. Open it to see all three tiers, each with a short description. Tiers your plan doesn’t include show a lock icon.

If you click a locked tier, you won’t hit a dead end: you’ll see a short note about which plan unlocks it (for example, “Smart AI needs Spark”) and a button to view plans. No error, no confusion — just a clear path to upgrade.

Choosing a tier per request

In the Co-writer composer (both the quick command bar and the chat panel), you can pick a tier for a single request without changing your usual setting:

Option	When to use it
Auto	Use your plan’s default tier
Fluent	Fast — drafts and quick rewrites
Smart	Balanced — everyday writing
Native	Top quality — final polish

This is handy on Pro: drop to Fluent for a quick grammar check to conserve your Native allowance, then use Native for the final polish.

Earn higher tiers through referrals

Free and Spark users can unlock better AI quality for a while by inviting friends:

Milestone	Reward
3 friends join	Smart AI for 14 days
10 friends join	Native AI for 30 days
25 friends join	Native AI for 90 days + 50,000 bonus words

While a boost is active, the boosted tier is available with no lock, the sidebar shows a boost indicator, and your Billing settings show a countdown. As it nears expiry, you’ll get a reminder about a week ahead and again in the final day. When it ends, your tier simply returns to your plan’s default — your work isn’t affected. If you upgrade to a paid plan, the boost is replaced by your new plan. See Referral program.

Quality vs. your monthly limits

Tier sets how good the AI is; your plan sets how much you can use. They’re separate:

• A Free user with a Smart boost gets Smart-quality results but still has Free-level monthly limits.
• A Pro user who drops to Fluent for a quick task still uses their Pro limits, just with Fluent-quality output.

Your usual tier choice is remembered on your device between sessions, and new devices start at your plan’s default. Per-request overrides are one-time and don’t change your usual setting.

Good to know

• Past results aren’t labeled with the tier that produced them.
• The tier applies across all tools (or per individual Co-writer request) — you can’t set, say, Fluent for grammar and Native for paraphrasing at the same time.
• You see tier names, not the underlying technology.
• Higher tiers come with your plan (or a referral boost) — you can’t buy a single Native request on its own.

Common questions

What’s the difference between Fluent and Native? Fluent is fast and capable for everyday tasks. Native produces publication-quality English — more natural phrasing, better academic tone, and fewer non-native artifacts. You’ll notice it most in paraphrasing, translation, and Co-writer output.

Can I try Native without paying? Yes, through referrals. Invite 3 friends for Smart for 14 days, or 10 friends for Native for 30 days.

Why would a Pro user switch to Fluent? To save their Native allowance. Simple tasks don’t need top quality — use Fluent for drafts and reserve Native for the final polish.

Does the tier affect all tools? Yes. Every AI-powered tool uses your selected tier.

What happens when my referral boost expires? Your tier returns to your plan’s default (Free → Fluent, Spark → Smart). Your documents and work are untouched — only future AI requests use the lower tier.

Can I change the tier mid-document? Yes. Use the switcher in the editor header any time, or override it for a single Co-writer request.

Is Max higher quality than Native? No — Max uses the same Native quality. What Max adds is 20× the monthly limits, maximum reasoning effort, and full cross-session memory. It’s more capacity and depth, not a new quality level.

Does the assistant remember my past chats? Yes, on every plan, but to different degrees. Free and Spark keep durable “Memories” (facts you save or confirm), while Pro and Max default to full cross-session recall.