Text to Speech for Dyslexia: What the Research Says

Text to speech for dyslexia may help some people understand written material. A 2018 meta-analysis found a small to moderate average gain in reading comprehension for students with reading disabilities. It is not a treatment for dyslexia and does not improve reading skill. Talk to a qualified professional about assessment and support.

This guide covers why listening can help, what the main studies found, what the research does not yet show, and which tools are worth knowing about as of October 2026.

Why can listening help with dyslexia?

Dyslexia is usually a difficulty with word reading, not with understanding spoken language. Wagner and colleagues (2020) make this distinction clear. They define unexpected poor reading as a gap of at least 1.5 standard deviations between listening comprehension and reading comprehension. A reader with that gap can often understand a passage when someone reads it aloud, even though decoding the words on the page is hard.

That is the reason listening-based support fits. Text to speech does not teach decoding. It gives access to the content of a text while the reader works on other skills. Wagner's paper also argues that dyslexia is better seen as a distribution that varies with severity than as a single number, which matters for the prevalence figures discussed below.

What did the main studies find?

Three sources make up most of the evidence discussed here. The table lists each one.

| Study | Who took part | Design | Finding | |---|---|---|---| | Wood, Moxley, Tighe and Wagner (2018), Journal of Learning Disabilities | Students with reading disabilities, grade 3 and above | Meta-analysis of 22 studies (total N 2,942 in the moderator table) | Average effect d = .35 (95% CI .14 to .56); d = .24 after adjusting for possible publication bias. Study design was the only significant moderator. Oral modality was not. | | Keelor and colleagues (2023), Annals of Dyslexia | Children aged 8 to 12 with reading and language difficulties | Five passages read under five conditions | Text to speech improved comprehension compared with no text to speech. Highlighting made no significant difference. Students with dyslexia gained more from text to speech and listen-only than students with reading plus language impairment. | | Canadian Journal of Learning and Technology (2023) | Students with learning disabilities | Literature review, not a primary study | Text to speech was used as a compensatory tool and linked to gains in reading speed, fluency and content retention. The review calls for training for students, educators and parents. |

The Wood meta-analysis is the largest of the three. Its authors concluded that text to speech "may assist students with reading comprehension". They also listed few randomised trials, small study counts and possible placebo and motivation effects as limits. Within the analysis, between-subject studies showed a larger effect (d = .61) than within-subject studies (d = .15, not significant). Read that as a reason for caution, not as a verdict.

Does word highlighting matter?

Highlighting, where each word lights up as it is spoken, is a common feature of reader apps. The evidence is thin. Keelor and colleagues found no significant difference between text to speech with highlighting and text to speech without it, in children aged 8 to 12. The Wood meta-analysis did not test highlighting. Both sets of authors call for more research, so do not assume highlighting helps a particular reader without trying it.

How common is dyslexia?

Estimates differ widely, and the reason is definitions. A 2022 meta-analysis by Yang and colleagues pooled 56 articles and reported a prevalence of 7.10% (95% CI 6.27 to 7.97%) for developmental dyslexia in primary school children. The rate was 9.22% for boys and 4.66% for girls. The authors note small samples and varied definitions.

| Source | Figure | What it measures | |---|---|---| | Yang et al. (2022), Brain Sciences | 7.10% (95% CI 6.27 to 7.97%) | Developmental dyslexia in primary school children, pooled from 56 articles | | Yale Center for Dyslexia and Creativity FAQ | "20 percent of the population" | A general population figure, with dyslexia said to account for 80 to 90 percent of people with learning disabilities |

Estimates depend on the definition used, the age group studied and the method of diagnosis. If you read a single figure in an article, check which definition it uses.

Tools to try

The tools below are the ones with the clearest published details. Prices and features change, so confirm them on the vendor's page.

| Tool | Cost as published (October 2026) | Notes | |---|---|---| | Microsoft Immersive Reader | Free | Built into Word, OneNote, Edge, Teams, Forms, Outlook and Excel. Offers read aloud, parts-of-speech highlighting, line focus in some apps and a picture dictionary. | | Microsoft Edge Read aloud | Not stated on the page read | Natural-sounding voices and accents. Works online, and offline with a few voices. Start from Settings, More, More tools, then Read aloud. | | Apple Spoken Content | Built in | On iPhone and iPad, choose voices and a speaking rate in Settings, Accessibility, Spoken Content. Menu names vary by iOS version. | | Bookshare | Free for qualified US students through an award from the US Office of Special Education Programs | Word-level highlighting and over a million titles. Non-student US individual membership is $79.99 a year. Eligibility is set by US copyright law, not by an IEP or 504 plan. | | Learning Ally | Price not shown on the home page | Over 80,000 human-narrated audio e-books for students with dyslexia and other print disabilities. | | Read&Write for Education | From $2.75 per seat, per the vendor's page | Text to speech with word highlighting. Free access for individual K-12 teachers. | | OndaLabs | Free plan at $0, with 2,000 credits (about 2 minutes) | Creates audio files from text you paste. It is not a reader app that follows the text. |

Sources: Microsoft Learning Tools, Edge Read aloud, Apple support, Bookshare, Learning Ally, Read&Write.

How to use text to speech well

Research on text to speech as an accommodation points to a few habits that matter more than the tool itself.

Pair listening with the printed text, so the reader sees and hears the same words.
Let the reader choose the speed and voice, where the tool allows it.
Start with short passages, then build up to longer readings.
Check comprehension with a few questions after listening.
Train the student, and the adults around them, to use the tool. The 2023 review links training to better use.

Where OndaLabs fits

OndaLabs is an audio production tool, not a reader app. A parent, teacher or adult can paste a worksheet, article or study notes into text to speech and get an audio file to listen to. The Free plan costs $0 and includes 2,000 credits, about 2 minutes, so you can try it first.

Three features may suit specific needs:

Two-speaker dialogue can turn study notes into a question-and-answer style audio. This is a possible format, not a research-backed method.
Custom voices, on Creator and above, can be made from a recording you have permission to use, such as a parent's or teacher's recording, through the voices page.
Commercial use is included from Starter, at $9 a month. This matters for teachers who sell materials, and not for personal study.

OndaLabs does not replace reader apps that follow the text with highlighting. For those needs, look at Immersive Reader, Edge, Apple's built-in tools and Bookshare. For more on tools, read read aloud tools for students and text to speech accessibility.

What the research cannot yet say

It does not show that text to speech treats or cures dyslexia.
It does not show that highlighting helps in general. The one study that tested it found no significant difference.
It does not give a single prevalence figure. Estimates vary with definitions.
It is not a substitute for a professional assessment. In the US, the IEP team must consider whether a child needs assistive technology devices and services under 34 CFR 300.324. That is general information, not legal advice.

This article is general information, not medical or educational advice. Talk to a qualified professional about assessment, accommodations and support for a specific reader.

Frequently asked questions

Does text to speech help people with dyslexia?

The evidence says it can help comprehension of material that is read aloud. The 2018 meta-analysis found a small to moderate average effect, and a 2023 study of children aged 8 to 12 found listening improved comprehension over silent reading. The research is about understanding text, not about learning to read it.

Is using text to speech cheating for a dyslexic student?

The studies here measure comprehension, not whether a tool is allowed. Whether a tool is permitted in a test or class is a school decision, and the rules differ by institution. Ask the school about its accommodation policy.

Does word highlighting help?

The evidence does not show a general benefit. A 2023 study of children aged 8 to 12 found no significant difference from highlighting, and the 2018 meta-analysis did not test it. Try highlighting with a reader and see whether it helps that person.

What is the best free text to speech for dyslexia?

There is no single best option. Microsoft Immersive Reader and Edge Read aloud are free, and Apple's built-in Spoken Content is available on iPhone and iPad. Bookshare is free for qualified US students. Match the tool to the reader's device, age and needs.

Can dyslexic students get audiobooks for free?

Some can. Bookshare is free for qualified US students through an award from the US Office of Special Education Programs, and eligibility is set by copyright law. Learning Ally offers over 80,000 human-narrated titles, but its price is not shown on the home page.

Do US schools have to consider assistive technology?

For students with an IEP, the team must consider whether the child needs assistive technology devices and services under 34 CFR 300.324. Text to speech can fall within that definition. This is general information, not legal advice, so ask the school how it applies the rule.