--- title: "What Is Automatic Speech Recognition? Definition" description: "What is automatic speech recognition? A plain definition, how it turns spoken audio into text, how word error rate measures accuracy and what to test." url: https://nexumautomations.com/glossary/speech-recognition updated: 2026-10-31 publisher: Nexum Automations, an AI consulting firm --- > Nexum Automations is an AI consulting firm that builds what it recommends. It finds where AI pays off in a company, builds it on the tools the team already uses and stays until it is live and working. Glossary # What is automatic speech recognition? Explained A plain definition of automatic speech recognition, how it works, how its accuracy is measured and how to test it on your own calls. Last reviewed October 30, 2026 Definition Automatic speech recognition Automatic speech recognition, often shortened to ASR, is software that turns spoken audio into written text. It is the first step behind call transcription and voice agents. **In short:** Software that turns speech into text. Our data ## What buyers see in this search The first page of Google for "what is automatic speech recognition", counted by type of result. | | Results | | ---------------------------------------------------- | ------------------------------- | | Articles by companies that sell a product or service | 8 of 9 | | Official, academic or standards sources | 1 of 9 | | Titles that answer this exact search | 9 of 9 | | Google features on the page | An AI Overview, People also ask | The 9 organic results on the first page of Google, United States, desktop, measured with DataForSEO on October 29, 2026\. Types only: no company or product is named. ## What it is and how it works 1. Capture Audio comes in from a call or recording. 2. Clean The sound is prepared and split into short pieces. 3. Match A model maps sounds to likely words. 4. Write Words are joined into readable sentences. Speech recognition listens to a recording or a live call and writes down the words it hears. The output is plain text a person or another system can read, search or act on. The process runs in a few steps. Each step passes its result to the next, from sound to words. The text it produces is only the starting point. Other software then works out what the words mean and what to do next. ## How speech recognition differs from similar terms * Speech recognition Turns spoken words into text. * Voice recognition Identifies who is speaking. * Language understanding Works out meaning and intent. Three terms get mixed up. Speech recognition answers one question: what words were said. Voice recognition answers a different one: who is speaking. It identifies a person from their voice, not the words. Language understanding comes after both. It works out the meaning and intent behind the text. See [natural language processing](https://nexumautomations.com/glossary/natural-language-processing) for that step. In a phone system, speech recognition feeds the rest. A menu-driven setup like [interactive voice response](https://nexumautomations.com/glossary/interactive-voice-response) can use it to take spoken answers instead of keypresses. ## How accuracy is measured Counted as errors * Wrong word swapped in * Word missing * Extra word added Hard on business calls * Noise and crosstalk * Accents and phone audio * Names and numbers Accuracy is usually reported as word error rate, or WER. Lower is better. In words, the formula counts three kinds of mistakes. Substitutions are words replaced by a wrong one. Deletions are words that went missing. Insertions are extra words that were never said. Add them up and divide by the number of words in a correct transcript. A Michigan State oral-history team notes that dictation by a steady speaker can reach about 5% word error rate or less, enough to get whole sentences right. The same source says even a 25% word error rate often does not hurt search quality much, because speech has plenty of redundancy. Business calls are harder than clean dictation. Background noise, accents, phone-line audio, names and numbers all push errors up. * Noise from offices, cars or open lines * Accents and fast or overlapping speech * Narrow phone-line audio quality * Names, product terms and spoken numbers ## Where it fits and what to test 1. Sample Gather real recordings from your lines. 2. Reference Prepare a correct transcript. 3. Compare Check errors on names and numbers. 4. Decide Set what a person still reviews. Speech recognition suits any job that starts with a spoken conversation. It writes up calls, feeds a [voice agent](https://nexumautomations.com/solutions/ai-voice-agent) and makes recordings searchable. A benchmark from someone else tells you little about your own calls. Test with your own recordings instead. Pick a sample that matches real use: your phone lines, your customers, your product names. Compare the output to a correct transcript and check where it slips, especially on names and numbers. FAQ ## Speech recognition questions * ### What is ASR? ASR stands for automatic speech recognition. It is software that converts spoken audio into text, the starting point for transcripts and voice systems. * ### How does speech recognition work? Audio is captured, cleaned and split into short pieces. A model matches them to likely sounds and words, then joins the words into sentences you can read. * ### What is considered a good WER? Lower is better, but it depends on the job. A Michigan State team says around 5% or less suits clean dictation, while a 25% rate can still support useful search. * ### What is ASR used for? Common uses of speech recognition technology are call transcription, voice assistants, meeting notes and searchable recordings. It is the speech-to-text layer inside voice agents. * ### Is speech recognition the same as voice recognition? No. Speech recognition works out which words were said. Voice recognition works out who is speaking. A system can use one, the other or both. --- Source: https://nexumautomations.com/glossary/speech-recognition Free AI diagnosis (30-minute call): https://nexumautomations.com/#book - Services: https://nexumautomations.com/services - Guides: https://nexumautomations.com/guides