Master the CLEAN Function: Remove Non-Printable Characters from Excel Text
=CLEAN(text)The CLEAN function is a powerful text manipulation tool in Excel that removes non-printable characters from text strings. Non-printable characters are invisible symbols that often appear when data is imported from external sources, web pages, or legacy systems. These characters can cause significant issues in data analysis, including formula errors, sorting problems, and inconsistent results. The CLEAN function strips away these problematic characters, leaving only visible, printable text that Excel can process correctly. When working with large datasets or imported information, you'll frequently encounter non-printable characters such as line breaks, tabs, and other control characters embedded within your text. These invisible elements can sabotage your data quality and create frustrating errors downstream. By applying the CLEAN function, you ensure your text data is sanitized and ready for analysis. This beginner-friendly function is essential for anyone working with data from multiple sources or preparing datasets for reporting and analysis.
Syntax & Parameters
The CLEAN function follows a simple syntax structure: =CLEAN(text). The function accepts a single required parameter, 'text', which represents the text string or cell reference containing the data you want to clean. This parameter can be a direct text value enclosed in quotation marks, a cell reference like A1, or a range reference that will be evaluated as text. When you execute the CLEAN function, it systematically removes all non-printable characters from the specified text while preserving all visible, printable content. Non-printable characters include control characters (ASCII values 0-31) and the delete character (ASCII 127). The function is particularly effective at removing line breaks, tabs, and formatting characters that often sneak into datasets during imports from external sources. Practical tips for using CLEAN effectively: First, always ensure your text parameter is properly referenced—use cell references rather than hardcoding text when possible for dynamic updates. Second, combine CLEAN with TRIM to remove both non-printable characters and excess spaces for maximum data cleanliness. Third, remember that CLEAN removes non-printable characters but does not remove leading or trailing spaces; use TRIM for that purpose. Finally, apply CLEAN early in your data processing workflow to prevent non-printable characters from causing downstream errors in formulas or analysis.
textPractical Examples
Cleaning Imported Customer Data
=CLEAN(A2)Cell A2 contains 'John\nSmith' with a hidden line break character. The CLEAN function removes this non-printable character, returning the properly formatted name 'John Smith' without the embedded line break.
Sanitizing Web-Scraped Product Descriptions
=CLEAN(B3)&" - "&CLEAN(C3)This formula cleans both the product name in B3 and category in C3, removing any non-printable characters from both cells before concatenating them with a space and dash separator.
Processing Survey Response Data
=CLEAN(D5)Survey response text in D5 contains multiple line breaks and tab characters from the form submission. CLEAN removes all these non-printable characters, leaving only the readable survey response text.
Key Takeaways
- CLEAN removes non-printable characters (ASCII 0-31 and 127) from text but does not remove regular spaces or leading/trailing whitespace
- Use TRIM(CLEAN(A1)) for comprehensive text cleanup that removes both non-printable characters and excess spaces
- CLEAN is essential for data imported from external sources, web scraping, or legacy systems that often contain hidden formatting characters
- Apply CLEAN early in your data preparation workflow to prevent non-printable characters from causing formula errors or data quality issues
- CLEAN is universally available across Excel, Google Sheets, and LibreOffice, making it a reliable function for cross-platform spreadsheet work
Pro Tips
Create a helper column with CLEAN formulas when processing large datasets. This preserves your original data while creating a cleaned version for analysis, allowing you to verify the cleaning process worked correctly.
Impact : Maintains data integrity and audit trail while ensuring you can troubleshoot any issues that arise from the cleaning process.
Combine CLEAN with SUBSTITUTE to remove specific non-printable characters you've identified. For example: =SUBSTITUTE(CLEAN(A1),CHAR(160)," ") replaces non-breaking spaces with regular spaces after cleaning.
Impact : Provides granular control over text cleaning and handles edge cases that CLEAN alone might not address completely.
Use CLEAN immediately after importing data from external sources (CSV files, web scraping, database exports). Make it the first step in your data preparation workflow to prevent non-printable characters from causing downstream errors.
Impact : Prevents cascading errors in formulas and ensures data quality from the earliest stage of processing, saving troubleshooting time later.
Test CLEAN on a small sample of your data first. Copy a few rows, apply CLEAN formulas, and verify the results before applying to your entire dataset. This helps identify any unexpected behavior or edge cases specific to your data source.
Impact : Reduces risk of widespread data transformation errors and ensures the cleaning approach is appropriate for your specific dataset characteristics.
Useful Combinations
Complete Text Cleanup: CLEAN + TRIM
=TRIM(CLEAN(A1))This powerful combination first removes all non-printable characters with CLEAN, then eliminates leading/trailing spaces and reduces multiple internal spaces to single spaces with TRIM. This is the gold standard for comprehensive text data cleaning before analysis or database import.
Conditional Cleaning with IF
=IF(LEN(A1)>0,CLEAN(A1),"")This formula checks if the cell contains any content before applying CLEAN. If the cell is empty, it returns an empty string; otherwise, it returns the cleaned text. This prevents errors when processing ranges with mixed empty and populated cells.
Multi-Step Data Transformation
=UPPER(TRIM(CLEAN(A1)))This combination cleans non-printable characters, removes excess spaces, and converts text to uppercase in one formula. Useful for standardizing imported data before creating lookup tables or reports. The order matters: CLEAN first, then TRIM, then UPPER.
Common Errors
Cause: The text parameter is omitted or the function is called without parentheses. Example: =CLEAN or =CLEAN()
Solution: Ensure you provide a valid text parameter within the parentheses: =CLEAN(A1). Verify that the cell reference or text string is properly specified.
Cause: The function name is misspelled or Excel doesn't recognize it. Example: =CLEN(A1) or =CLEANUP(A1)
Solution: Double-check the spelling of the function name. It must be exactly 'CLEAN' in uppercase. Use autocomplete by typing '=CLE' and selecting from the dropdown menu.
Cause: The cell reference provided in the text parameter refers to a deleted column or invalid range. Example: =CLEAN(Z999) when Z999 doesn't exist.
Solution: Verify that the referenced cell exists and contains data. Update the formula with a valid cell reference. Use the Name Box to navigate and confirm cell locations.
Troubleshooting Checklist
- 1.Verify the text parameter is correctly referenced—check that cell references exist and contain data
- 2.Confirm CLEAN is spelled correctly and the function is recognized by Excel (check for #NAME? error)
- 3.Test with a simple cell reference first (=CLEAN(A1)) before using complex nested formulas
- 4.Combine with TRIM if spaces remain after cleaning: =TRIM(CLEAN(A1))
- 5.Check if the non-printable characters are actually removed by comparing cell lengths before and after using LEN function
- 6.Ensure you're not confusing CLEAN with other text functions like TRIM, SUBSTITUTE, or LOWER that serve different purposes
Edge Cases
Cleaning text that contains only non-printable characters
Behavior: CLEAN returns an empty string, as there are no printable characters remaining after removal
Solution: Use IF to check for empty results: =IF(LEN(CLEAN(A1))=0,"[No printable content]",CLEAN(A1))
This edge case is rare but can occur with corrupted data or certain system-generated files
Applying CLEAN to cells containing numbers or formulas
Behavior: CLEAN converts numbers to text strings and removes any non-printable characters. Formula results are converted to their text representation first.
Solution: If you need to preserve numeric values, use VALUE() after CLEAN: =VALUE(CLEAN(A1)) to convert back to numbers
This is important for maintaining data types in subsequent calculations
Using CLEAN on very large text strings (>32,767 characters)
Behavior: Excel has a cell content limit of 32,767 characters. CLEAN will process the text but may be truncated if it exceeds this limit.
Solution: For extremely large text, consider processing data outside Excel or breaking it into smaller chunks before applying CLEAN
This limitation is rare in typical business scenarios but important for text mining or document processing applications
Limitations
- •CLEAN does not remove regular spaces or leading/trailing whitespace—use TRIM for that purpose or combine both functions with =TRIM(CLEAN(A1))
- •CLEAN cannot selectively remove only certain non-printable characters; it removes all of them—use SUBSTITUTE if you need to target specific characters
- •CLEAN converts the result to text format, which may affect subsequent numeric calculations; wrap with VALUE() if numeric results are needed
- •CLEAN does not provide visibility into which non-printable characters were removed; use LEN comparison or character analysis tools if you need detailed information about removed characters
Alternatives
Provides powerful pattern-based character removal using regular expressions. More flexible than CLEAN for complex scenarios.
When: Google Sheets users can use REGEX to remove multiple types of characters in one formula. Example: =REGEX(A1,"[^\x20-\x7E]","","g") removes all non-ASCII printable characters.
Compatibility
✓ Excel
Since 2007
=CLEAN(text)✓Google Sheets
=CLEAN(text)Fully compatible with Google Sheets. Works identically to Excel version. Can be combined with REGEX for more advanced character removal.
✓LibreOffice
=CLEAN(text)