Check the full stereo file for opposite polarity, then invert the left, right, or both channels without reversing playback.
Drop audio here, or click to select
Audio and video files are processed locally in your browser and are not uploaded.
Audio polarity inversion multiplies every sample in the selected channel by -1. It flips the waveform vertically while preserving timing, pitch, and playback direction.
If one stereo channel closely matches the negative of the other, written as L ≈ -R, shared content can become very quiet or disappear when the channels are combined to mono. Inverting either one channel restores their relative polarity.
The detector evaluates the complete audio timeline rather than only the beginning. It excludes silent and extremely quiet sections, measures correlation, level matching, mono fold-down loss, and time coverage, and reports cases where opposite polarity appears only in parts of the file.
A stereo comparison cannot determine which side has the intended absolute polarity. Invert either the left or right channel to repair relative cancellation; inverting both usually preserves the same left-versus-right relationship. Preview the result before exporting. Processing stays in this browser tab.
Polarity inversion multiplies every sample in the selected channel by -1. The waveform flips vertically, but its timing, pitch, and playback direction stay the same. Reversing audio instead changes the order in which samples play.
When the right channel closely matches the negative of the left channel, combining them to mono can make shared content much quieter or cancel it almost completely. Inverting either one channel restores their relative polarity. Inverting both does not repair that cancellation.
The check samples the complete audio timeline, ignores silent and extremely quiet sections, and evaluates correlation, level matching, mono fold-down loss, and how consistently the condition appears. It reports partial or uncertain cases separately instead of treating every negative correlation as a fault.
The analysis can identify the relationship between the left and right channels, but it cannot know which channel has the intended absolute polarity. If the channels are matching opposites, invert either the left or the right channel, preview the result, and keep the choice that fits your signal chain.
Choose Fill both channels and select the side containing sound. That side is copied to both outputs. This differs from a true mono input: a stereo file may contain two channels with one silent.
Related tools: Audio Channel Converter · Stereo to Mono · Mono to Stereo · Extract Left · Extract Right · Swap Channels
Format and beautify Java, Python, JavaScript, JSON, HTML and more; adjust indentation, spacing and line breaks.
Inspect, compare and validate JSON; test JSONPath expressions, or convert data to CSV, YAML and XML.
Open and edit CSV or Excel sheets, format tabular text, and convert CSV to Excel or SQL.
Write and preview Markdown, render Mermaid diagrams, and convert Markdown, HTML and tables between formats.
Compare passages, count words and keywords, sort or replace lines, and view DOCX text.
Convert between MP3, WAV, FLAC and more, play audio or raw PCM, and inspect or edit audio metadata.
Trim, join or split recordings, remove silence or noise, and adjust volume, speed, pitch or channels.
Transcribe audio to text, generate speech from text, or record your voice in the browser.
Convert and compress video, trim or join clips, resize frames, and extract audio.
Play local or streaming video, record your screen or camera, and use your camera as an online mirror.
Compress or merge PDFs, split and rearrange pages, convert pages to images, and view or compare documents.
Convert image formats, resize or crop photos, compress files, compare pictures, and extract text with OCR.
Capture and beautify screenshots, turn text into images or GIFs, draw on a whiteboard, and create word clouds or favicons.
Edit SRT or VTT captions with a video preview, shift timing, convert formats, and manage subtitle tracks.
Open ZIP, 7Z, RAR or TAR files, extract selected contents, and create new archives with optional ZIP/7Z passwords.
Encode and decode Base64 or Base32, escape URLs, HTML and Unicode text, and inspect JWT contents.
Convert number bases and values between binary, decimal and hex; turn numbers into words or text into binary.
Work out percentages and fractions, summarize statistics, and calculate grades, discounts or aspect ratios.
Show an online clock, run a countdown or stopwatch, and calculate dates, ages or time-zone differences.
Check your IP and IPv6 connection, inspect HTTP requests or HAR files, and calculate CIDR address ranges.
Convert length, weight, temperature, data storage and other units.
Convert HEX, RGB and HSL values, extract colors from an image, check contrast, or test your display with solid colors.
Generate and scan QR codes or barcodes, including QR codes for links and Wi-Fi networks.
Generate hashes, UUIDs and passwords, test regular expressions, create URL slugs and check file permissions.
Check screen resolution and refresh rate, measure with a screen ruler, test keys, or read from a teleprompter.
2048, Minesweeper, Sudoku, Gomoku, Tank Battle