What exactly are filler words and why do they matter?

Filler words are unconscious sounds or phrases — "um," "uh," "like," "you know," "basically" — that speakers insert while searching for their next word. They matter because research consistently shows they reduce perceived confidence and credibility, lower IELTS fluency scores, and can undermine job interview performance — regardless of how strong the underlying content is.

How long does it take to stop using filler words in English?

With consistent, real-time feedback, most learners see a measurable reduction in filler frequency within 2–4 weeks of daily practice — around 15–20 minutes per session. Without targeted feedback, the habit can persist indefinitely because you don't catch it in the moment. The speed of improvement is directly tied to how quickly after the error you receive correction.

Can I fix filler words by just slowing down my speech?

Slowing down helps slightly but doesn't eliminate the habit on its own. Fillers happen because the brain needs processing time, and slowing down gives it marginally more. But the core issue is an automatic habit — you don't consciously decide to say "um." Breaking it requires awareness and corrective feedback at the moment it happens, which is why real-time AI coaching is more effective than simply trying to speak slower.

Are filler words in English different from my native language's fillers?

Yes, and this matters. Many learners who are filler-free in their native language develop new filler habits in English because the cognitive load of speaking a second language increases dramatically. Your English fillers may be completely different from your L1 fillers — so strategies that worked in your native language may not transfer directly. English-specific AI coaching targets your English speech patterns specifically.

Do English native speakers also use filler words?

Absolutely — native speakers use fillers constantly. Research puts average filler frequency at around once every 4–5 seconds in spontaneous speech. The difference is that in professional and high-stakes contexts, fluent speakers learn to replace fillers with deliberate pauses. That's the skill being trained — not the elimination of all hesitation, but the ability to pause instead of fill.

Will reducing filler words make me sound too formal or robotic?

No. The goal isn't silence — it's replacing unconscious "um" with purposeful pausing. A brief pause sounds thoughtful and confident, not robotic. You'll still speak naturally; you'll just stop adding acoustic noise that signals uncertainty. Most learners find their speech sounds more natural once fillers drop, because listeners can follow the actual content without filtering out the noise.

How does AI track filler words during speaking practice?

AI speech coaches process your audio in real time using speech recognition and pattern detection. The system identifies specific words and sounds that match known filler patterns — "um," "uh," "like," "you know," etc. — and logs their frequency and timing. After each session, you receive a breakdown of which fillers appeared, how often, and in what contexts. Over multiple sessions, the platform tracks whether your frequency is declining.

Stop Saying "Um" and "Like": How AI Can Train Away Your Filler Words

Apr 10, 2026

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8 min read

Quick Answer: Filler words like "um," "like," and "you know" are unconscious habits that undermine your spoken confidence and credibility in English. The fastest way to eliminate them is real-time feedback — catching yourself in the moment, not hours later. AI-powered tools like Stimuler now deliver that feedback instantly, making it possible to improve speaking English far faster than traditional practice methods.

Introduction

Picture this: you're mid-sentence in a job interview, explaining why you're the right candidate, when it happens — "So, um, I have, like, five years of, you know, experience in this field." The words are right. The confidence? Gone.

Filler words are the silent killers of spoken English. They sneak into your speech before you even notice them, and by the time you do, the interviewer has already formed an impression. Most learners know they have the problem. They just don't know how to fix it — because traditional practice gives you zero feedback on fillers in real time.

This post is about changing that. You'll learn exactly why filler words happen, how the brain gets stuck in the habit loop, and — most importantly — how AI coaching can finally train them out of your speech for good.

Why Filler Words Happen (It's Not Laziness)

Let's clear something up first: saying "um" doesn't mean you're unsure of yourself or poorly educated. It means you're human.

Filler words (also called disfluencies) are sounds or phrases — "um," "uh," "like," "you know," "basically," "right?" — that speakers use to hold conversational space while their brain searches for the next word. Linguists have studied them for decades. Research from Columbia University found that the average speaker uses filler words roughly once every 4–5 seconds in spontaneous conversation. That's a lot of "um."

The problem gets worse in a second language. When you're speaking English as a non-native speaker, your brain is doing double duty: translating thoughts, selecting vocabulary, monitoring grammar, tracking pronunciation — all simultaneously. Fillers are the brain's coping mechanism. They buy time.

So why doesn't just "thinking before you speak" solve it? Because the habit is automatic. By the time your conscious brain registers the "um," your mouth has already said it. You can't outthink a reflex.

This is where most self-study methods fail. Watching videos, reading tips, even practising with a friend — none of these give you immediate feedback at the exact moment the filler slips out. And without that immediacy, the habit doesn't break.

According to a 2022 study from the University of Rochester, language habits require spaced, corrective feedback to rewire — you need to be corrected immediately and repeatedly, not once every few days.

The Real Cost of Filler Words in English

It's tempting to think fillers are just a minor style issue. They're not. The research is blunt:

A Princeton University study found that speakers who used frequent fillers were rated as less competent, less confident, and less credible than those who used strategic pauses instead. The words themselves were identical. Only the fillers changed — and the perception changed dramatically.

For non-native English speakers, the stakes are even higher. In an IELTS speaking exam, excessive fillers directly lower your fluency score. In a job interview at an international company, they signal hesitation even when you're completely sure of your answer. In everyday conversation, they make you sound uncertain when you're not.

Here's what's happening from the listener's side: human brains are pattern-matching machines. When someone hears "um" repeatedly, the brain flags it as a signal of low confidence — even subconsciously. It doesn't matter whether that's fair. It happens.

The good news? Fillers are one of the most trainable aspects of spoken English. Unlike accent or grammar, they're purely habitual. Remove the habit, and your speech sounds instantly more polished — even if nothing else changes.

How AI Can Actually Fix the Problem

Why Traditional Methods Fall Short

Before we get to the solution, it's worth understanding why the usual advice doesn't work:

"Record yourself and listen back" — You hear the fillers after the fact. The habit doesn't change.
"Ask a friend to tap the table every time you say um" — Disruptive, awkward, and unsustainable in real conversation.
"Think before you speak" — Impossible in spontaneous speech. By definition.

What works is real-time, specific, consistent feedback — the exact moment a filler escapes, you know about it.

How AI Coaching Delivers What Humans Can't

This is where AI tools like Stimuler's AI coach, Sarah, change the equation. Here's how real-time AI speech coaching tackles filler words step by step:

You speak. You have a practice conversation, answer a prompt, or run through an IELTS mock question.
The AI listens in real time. Unlike a recording you review later, the model processes your speech as it happens.
Specific feedback lands immediately. You're told exactly which fillers you used, how often, and at which moments — not as a general "you said um a lot" but with timestamps and patterns.
You repeat the same prompt. With the feedback fresh, you try again. The gap between the correction and the next attempt is seconds, not days.
Over sessions, the pattern breaks. Each session, the AI tracks whether your filler frequency is dropping — giving you visible progress data that keeps you accountable.

Research from Stanford's language lab found that real-time corrective feedback accelerates habit change 3–4x faster than delayed feedback. That's the core advantage AI brings to this problem.

What Most Learners Miss: The Pause Replacement Strategy

Cutting fillers without replacing them creates a new problem: awkward silence panic. Most people reach for "um" because silence feels uncomfortable. They fear it signals confusion. So they fill it.

Here's what fluent speakers actually do: they pause deliberately. A 1–2 second pause sounds like confidence. "Um" sounds like uncertainty. The content is identical; the perception is completely different.

When you improve speaking English with AI coaching, the goal isn't just to remove fillers — it's to replace them with purposeful pausing. Some platforms let you practise this explicitly, giving you prompts where you're coached not to speak until you're ready, training your brain that silence is safe.

A Few Other Patterns Worth Knowing

"Like" as an approximator ("It was, like, three hours") is different from "like" as a filler ("I was like, um, going to…"). Awareness of the difference helps you catch the problematic ones.
"Basically" and "literally" are stealth fillers — they sound purposeful but often add zero meaning. Track them separately.
Topic-triggered fillers — many speakers are only filler-heavy on certain topics (complex technical subjects, emotional topics, anything that requires thinking on the spot). Knowing your trigger zones helps.

If you're preparing for the IELTS speaking exam, our IELTS speaking guide on the Stimuler blog goes deep on how examiners score fluency and what patterns cost you points in Part 2 and Part 3.

How Stimuler Helps You Train Away Fillers

Stimuler's AI coach Sarah is built specifically for spoken English — not reading comprehension, not vocabulary flashcards. Every session is a conversation, and every conversation generates a detailed breakdown of your speech.

Here's what that looks like in practice for filler word training:

Sarah tracks your filler word frequency as a dedicated metric alongside pronunciation, pace, vocabulary range, and grammar. You don't have to ask for feedback on fillers — it's part of every session's report automatically.

The platform's conversation topics are designed to simulate real-world pressure scenarios — job interviews, IELTS Part 2 cue cards, everyday conversation, professional meetings. These aren't easy, controlled topics where fillers naturally disappear. They're the kinds of conversations where your filler habits surface most — and that's exactly where you need to break them.

At around $5–7/month, Stimuler brings this kind of detailed AI coaching to over 1 million learners across 200+ countries — people who don't have access to expensive human tutors but need serious, measurable improvement.

You can check out how we compare to other apps through our reviews of ELSA Speak vs Stimuler and Speak vs Stimuler 2026 if you want a side-by-side before deciding.

7 Actionable Tips to Stop Saying "Um" and "Like"

Audit your speech first. Record a 2-minute talk on any topic, then count your fillers. You can't fix what you haven't measured. Most people are shocked — the number is always higher than they think.
Pick one filler to eliminate at a time. Trying to stop all fillers simultaneously is overwhelming. Start with your most frequent one. Once that drops, move to the next.
Train yourself to hear it. For one week, notice fillers in other people's speech — podcasts, YouTube, conversations. This heightens your sensitivity to the pattern so your brain starts catching it in your own speech.
Replace fillers with breath. Every time you feel an "um" coming, take a breath instead. Breathing gives your brain the same processing pause without filling the silence with noise.
Practice under pressure deliberately. Fillers spike when you're under stress. Practice prompts that make you think hard — opinion questions, hypotheticals, unfamiliar topics. This is where AI coaching platforms like Stimuler earn their value.
Use the read-aloud technique. Read a passage aloud daily, but stop at every comma for a full second. This trains your brain that pausing mid-thought is acceptable and even sounds polished.
Track weekly, not daily. Day-to-day filler count varies based on topic difficulty and tiredness. Track weekly averages to see real trends. Consistent AI sessions give you this data automatically.

If you want to understand how human tutors compare to AI coaching for this kind of structured practice, our Preply vs Stimuler comparison breaks it down honestly.

Conclusion

Filler words aren't a language problem — they're a habit problem. And like all habits, they respond to one thing above everything else: immediate, consistent, specific feedback.

The reason traditional methods fail is simple: they give you feedback too late, too infrequently, or not at all. Recording yourself and reviewing it later is useful, but it's not the same as being told, in the moment, that you just said "um" for the fourteenth time this session.

AI-powered English coaching has closed that gap. Platforms like Stimuler give you real conversations, real-time speech analysis, and session-by-session progress tracking that makes the invisible visible. Your fillers become data. Data becomes habits. Habits become confidence.

If you want to improve your speaking English and actually sound as capable as you are, the first step is honest feedback. Start with Stimuler — your AI coach Sarah is ready when you are.