MX Player Subtitles Show as Boxes or Question Marks: Encoding Fix Guide

Seeing little squares, boxes, or question marks in MX Player subtitles usually means one of two things: the subtitle text is being decoded with the wrong character encoding (for example, UTF-8 read as Windows-1252), or the selected subtitle font does not contain the glyphs for the language you are watching. The good news is that you can fix both problems quickly, and you do not need to re-download your video. This guide walks through practical, reliable fixes on Android, explains why the problem happens, and shows how to permanently prevent it.

1. What Boxes Or Question Marks Actually Mean

Those “□□□” boxes (sometimes called tofu) and “????” characters are not random glitches. They are visible symptoms of one of these issues:

• Wrong subtitle character encoding: The subtitle file is plain text. If it was saved as UTF-8 but the app reads it as a different encoding (or vice versa), characters outside basic ASCII can become question marks, accented letters can turn into symbols, or entire non-Latin scripts can break.
• Missing glyphs in the subtitle font: Even if the subtitle file is correctly encoded, the font MX Player uses might not include the characters for your language (common with Chinese, Japanese, Korean, Arabic, Thai, Hindi, and others). When the font cannot draw a character, many systems display a box.
• Corrupted or poorly formatted subtitle file: Less common, but possible. A broken file, wrong file type, or malformed lines can cause unexpected rendering.

The key to fixing it is determining whether your problem is encoding, font coverage, or both. In practice, you can try the fast MX Player setting changes first, then move to converting the subtitle file if needed.

1.1 Boxes Versus Question Marks: A Quick Diagnosis

Use this as a rule of thumb:

• Mostly boxes (□ □ □): Often a font glyph problem, especially for non-Latin scripts.
• Many question marks (????): Often an encoding problem or a “lossy” conversion that replaced unknown characters with “?”.
• Weird symbols like é instead of é: Classic sign of UTF-8 read as Windows-1252 (or similar mismatch).

It is still possible to have both issues at the same time, particularly when subtitles were downloaded from different sources or edited multiple times.

2. Fix It Inside MX Player First (Fastest Options)

Before editing files, try changing MX Player’s subtitle settings. Depending on your MX Player version and Android device, the exact menu names may vary, but the options are typically located in subtitle settings while a video is playing.

2.1 Change Subtitle Text Encoding (If Available)

Some builds of MX Player offer a subtitle text encoding selection. If you see an “Encoding” option, it is one of the quickest fixes.

1. Open the video in MX Player.
2. Open the Subtitle menu (often via the on-screen menu).
3. Look for Text encoding or Encoding.
4. Try UTF-8 first.
5. If UTF-8 does not fix it, try encodings that match your subtitle source, such as Windows-1252 (Western European), Windows-1251 (Cyrillic), ISO-8859-2 (Central European), GBK/GB2312 (Simplified Chinese), Big5 (Traditional Chinese), or Shift_JIS (Japanese).

If changing encoding instantly makes the subtitles readable, your file was likely saved correctly but MX Player auto-detected the wrong encoding.

2.2 Switch The Subtitle Font (Common Fix For Boxes)

If the encoding is correct but you still see boxes, you likely need a font with broader Unicode coverage.

1. While the video is playing, open subtitle settings.
2. Find Font (or Subtitle font).
3. Switch to a different font if available.
4. If MX Player supports a custom font option, select a font file that supports your language.

Practical tip: fonts such as Google’s Noto families are designed for wide Unicode coverage. If you are regularly watching subtitles in multiple languages, using a wide-coverage font can prevent recurring issues.

2.3 Confirm You Are Using The Correct Subtitle Track Or File

If you have multiple subtitle files (or embedded subtitle tracks), you may be viewing a broken track while a working one exists.

• In subtitle settings, check Subtitle track or Select subtitle.
• Try another track, especially if one is labeled with your language.
• If you loaded an external subtitle, try reloading it and ensure the file is not zero bytes.

If another track displays correctly, the “boxes or question marks” issue is isolated to a specific subtitle file rather than MX Player itself.

3. The Real Root Cause: Subtitle Encodings Explained Simply

Most subtitle files (especially .srt) are plain text. Plain text is just bytes, and the encoding is the mapping that tells a program how to interpret those bytes as characters. If MX Player guesses the wrong mapping, characters can break.

3.1 Why UTF-8 Is Usually The Best Choice

UTF-8 is a Unicode encoding that can represent characters from virtually every writing system and is the most common encoding on the modern web. When you save subtitles as UTF-8, you dramatically reduce the chance of display problems across apps and devices.

• It is widely supported on Android and modern media players.
• It handles mixed-language subtitles well (for example, English plus Japanese names).
• It avoids the limitations of older single-byte encodings.

That said, a subtitle file can be valid and still not be UTF-8. Many older subtitle sources use Windows code pages like 1252 or regional encodings like Shift_JIS.

3.2 “ANSI” Is Not A Real Encoding (But You Will See It)

Many Windows tools show “ANSI” as an encoding option. In practice, that typically means “use the system’s current legacy code page,” which varies by region and settings. This ambiguity is one reason subtitles saved as “ANSI” can look correct on one computer and break on another phone.

If you want predictable results, convert subtitles to UTF-8 explicitly.

4. Convert Subtitles To UTF-8 (Most Reliable Long-Term Fix)

If changing MX Player settings does not solve it, convert the subtitle file to UTF-8. This is the most reliable solution because it fixes the file itself, not just playback on a single device.

4.1 Convert To UTF-8 Using Notepad++ (Windows)

Notepad++ is a widely used text editor that makes encoding conversion straightforward.

1. Open the subtitle file (for example, movie.srt) in Notepad++.
2. Go to the Encoding menu.
3. Try Character sets or Encode in options if the text looks wrong.
4. Once the text displays correctly, choose Convert to UTF-8 (or Convert to UTF-8-BOM if you need BOM for compatibility).
5. Save the file.
6. Copy it back to your phone and reload it in MX Player.

Important: “Convert to UTF-8” is different from “Encode in UTF-8” depending on the tool and current state. The goal is to first interpret the file correctly, then convert it and save.

4.2 Convert Using Subtitle Edit (Windows)

If you also want to validate subtitle formatting, fix timing, or ensure the file is clean, Subtitle Edit is a strong option.

1. Open the subtitle in Subtitle Edit.
2. Check whether it detects the encoding correctly.
3. Save or “Save as” and choose UTF-8 as the encoding.

This is particularly helpful if the file has stray control characters or formatting oddities.

4.3 Convert Using iconv (macOS, Linux, Or Power Users)

If you know (or can guess) the source encoding, you can convert very reliably with iconv in a terminal.

Example conversions:

• Windows-1252 to UTF-8: iconv -f WINDOWS-1252 -t UTF-8 input.srt > output.srt
• Shift_JIS to UTF-8: iconv -f SHIFT_JIS -t UTF-8 input.srt > output.srt
• GBK to UTF-8: iconv -f GBK -t UTF-8 input.srt > output.srt

If you choose the wrong “from” encoding, the output will still look wrong. If you are unsure, open the file in a capable editor and experiment until characters display correctly before converting.

5. Fix Boxes Caused By Missing Fonts (Glyph Coverage)

If your subtitle file is UTF-8 and still shows boxes, the issue is often font coverage. A font must contain the glyph for each character. If it does not, you see a fallback symbol such as a box.

5.1 Use A Font That Supports Your Language

For broad subtitle compatibility, pick a font family designed for extensive Unicode coverage. Google’s Noto project is a common go-to because it aims to cover “all” languages.

• Install or copy a compatible font file to your device (if MX Player supports custom fonts).
• Select that font in MX Player subtitle settings.
• Re-test the same subtitle segment that previously showed boxes.

If the boxes disappear but some characters remain broken, you may be mixing scripts that require different fonts or the subtitle contains unusual symbols not supported by your chosen font.

5.2 Distinguish Font Problems From Encoding Problems

Here is a practical test:

• If Latin text (A-Z) displays fine but Chinese characters show boxes, it is usually a font issue.
• If Chinese characters show as random Latin symbols, it is usually an encoding issue.

This distinction helps you avoid wasting time converting encodings when you actually need a better font.

6. Subtitle File Type Matters: SRT, ASS, SSA, VTT

MX Player commonly plays external subtitles such as .srt and .ass (Advanced SubStation Alpha). The file type does not automatically determine the encoding, but it can affect how fonts and styling are handled.

6.1 SRT Is Simple And Common (But Often Poorly Encoded)

SRT files are typically plain text with timestamp lines and dialogue lines. Because they are so simple, they are often shared without consistent encoding standards, especially on older subtitle sites.

• Best practice: save SRT as UTF-8.
• Avoid “ANSI” saves when possible.

6.2 ASS Or SSA Can Specify Fonts (Which Can Backfire)

ASS/SSA subtitles can include style lines that specify a particular font name. If that font does not exist on your Android device, the player may substitute another font that lacks the needed glyphs, causing boxes.

If you suspect this:

1. Open the ASS file in a subtitle editor.
2. Inspect the style font name.
3. Change it to a font you actually have, or remove the forced font styling.

This is a common reason “fansub” ASS files look perfect on a PC configured with the right fonts but break on a phone.

7. Step-By-Step Troubleshooting Checklist (Do This In Order)

If you want a clean sequence that solves most cases with minimal effort, follow this order:

7.1 Quick MX Player Checks

1. Switch to a different subtitle track (embedded or external).
2. Look for a subtitle Encoding option and try UTF-8.
3. Change the subtitle font to a known multilingual font.

7.2 File Fixes (If It Still Breaks)

1. On a computer, open the subtitle in Notepad++ or Subtitle Edit.
2. Identify the encoding that displays text correctly.
3. Convert and save as UTF-8.
4. If using ASS/SSA, remove or adjust the forced font style.
5. Re-copy to your device and retest in MX Player.

7.3 Last-Resort Checks

• Try another media player to confirm whether the subtitle file is truly broken.
• Download a different subtitle release for the same video (preferably labeled UTF-8).
• If the file was edited, ensure it was saved without replacing characters with “?”. Once characters are replaced, converting to UTF-8 cannot recover the original text.

8. Prevent The Problem: Best Practices When Downloading Or Creating Subtitles

If you frequently watch content with subtitles, you can avoid most “boxes and question marks” problems by standardizing your workflow.

8.1 Always Prefer UTF-8 Subtitles

When you have a choice, pick subtitle downloads that explicitly mention UTF-8. If you create subtitles, save them in UTF-8 from the start. This reduces guesswork and improves cross-device playback.

8.2 Keep A Known-Good Subtitle Font Handy

Many subtitle issues are not about encoding at all. Keep a high-coverage font available so you can quickly set it in MX Player when a subtitle uses a script your current font does not support.

8.3 Avoid Tools That Hide Encoding Details

Some basic editors obscure what encoding you are using and silently apply regional defaults. Prefer tools that make encoding explicit and let you convert safely (for example, Notepad++ or dedicated subtitle editors).

9. Common Questions About MX Player Subtitle Encoding

9.1 Why Do Subtitles Look Fine On My PC But Not On My Phone?

Two common reasons:

• Your PC player may automatically detect the encoding correctly, while MX Player guesses differently.
• Your PC may have fonts installed that your phone does not, so the PC can render glyphs that the phone cannot.

9.2 Should I Use UTF-8 Or UTF-8-BOM?

UTF-8 without BOM is the modern default. However, some software uses the BOM as a hint for encoding detection. If MX Player or your workflow struggles to detect UTF-8 reliably, saving as UTF-8-BOM can help in some cases. The best choice depends on what your player recognizes consistently.

9.3 Can I Fix This Entirely On Android Without A Computer?

Sometimes. If MX Player offers encoding selection and custom fonts, you can fix many cases without converting files. For full reliability, converting the subtitle to UTF-8 using a capable editor is still the most dependable approach, and that is often easier on a desktop.

9.4 If Characters Turned Into “?” Can I Recover Them?

Usually not. A question mark often means the character was replaced during a lossy conversion or save. If you still have the original subtitle source, go back to that original and convert it properly to UTF-8 instead of re-saving a damaged file.

10. A Practical “Works Almost Every Time” Fix Recipe

If you want a single, repeatable method that solves the majority of MX Player subtitle box and question mark issues, do this:

1. Open the subtitle file in Notepad++.
2. Select an encoding that makes the text readable.
3. Convert it to UTF-8 and save.
4. In MX Player, set a subtitle font with strong Unicode coverage.
5. Reload subtitles and verify problematic lines.

This approach addresses both the decoding side (encoding) and rendering side (font glyphs). Once you do it once or twice, you can fix most subtitle files in a couple of minutes.

Citations

• Unicode FAQ: UTF-8, UTF-16, UTF-32 and BOM. (Unicode.org)
• Notepad++ Documentation (Editing and encodings). (Notepad++ User Manual)
• Subtitle Edit (features and documentation). (GitHub)
• Google Noto Fonts (Unicode coverage goals). (Google Fonts)
• iconv overview and usage (character set conversion). (GNU libiconv)