Skip to main content
Data Cleaning

Messy spreadsheet? Clean it in clicks — no Python, no Alteryx, no code.

Remove Duplicates, Fix Casing, Filter Rows — All Without Writing a Line of Code

Business analysts and Excel power users spend hours manually cleaning data — deleting duplicate rows, fixing inconsistent capitalization, removing empty cells, trimming trailing spaces. Diwadi does all of this automatically, locally on your computer, in seconds. Works with CSV, Excel, and Parquet files.

Common Data Quality Problems That Slow You Down

Before you can analyze data, you have to clean it. Studies find that data professionals spend 60–80% of their time on data preparation. Here are the most common problems in real-world spreadsheets:

Duplicate Rows

Duplicates are pervasive — industry studies estimate 10–30% of records in large datasets are duplicates. A CRM export might have the same customer 3 times with slightly different email addresses. A survey might have repeated submissions. Duplicates silently inflate counts, skew averages, and corrupt analysis.

Empty Rows and Missing Cells

Exported spreadsheets often contain blank rows between sections, empty header rows, or records with key fields missing. Formulas break on empty cells. Pivot tables miscount. Joins fail. Manual deletion is tedious and error-prone on files with thousands of rows.

Inconsistent Text Casing

"New York", "new york", "NEW YORK", and "New york" are treated as four different values by any database or formula. This breaks GROUP BY queries, VLOOKUP matching, and pivot table grouping. Cities, country names, product categories, and job titles are all common victims of inconsistent casing.

Extra Whitespace

A space before or after a word is invisible in a spreadsheet but breaks exact matching. "Apple " and "Apple" will not match in VLOOKUP, SQL JOIN, or deduplication. Imported data from forms, APIs, and legacy systems routinely includes leading and trailing spaces.

Mixed Date Formats

One column might contain "2024-01-15", "01/15/2024", "January 15 2024", and "15-Jan-24" — all representing the same date. Sorting fails, date arithmetic breaks, and filters don't work across mixed formats. This is especially common in data exported from multiple systems.

Special Characters and Encoding Issues

Names with accents, currency symbols, smart quotes, and non-breaking spaces cause import failures, broken formulas, and database errors. Data exported from older systems or different locales often has encoding artifacts that need to be stripped or standardized.

The Old Way vs. The Diwadi Way

Tool Skills Required Annual Cost Large Files Data Privacy
Python / pandas Coding knowledge required — pandas, Jupyter, environment setup Free (but your time isn't) Fast for large files Local — data stays on your machine
Alteryx Drag-and-drop but complex workflow builder $5,195 / year minimum Excellent — built for enterprise data Depends on deployment (cloud vs. desktop)
Excel (manual) Basic — but repetitive and error-prone $99–$150 / year (Microsoft 365) Crashes or slows on files over 100K rows Local — data stays on your machine
OpenRefine Moderate — complex UI, steep learning curve Free Handles large files but slow on very large datasets Local — runs in browser via local server
Diwadi None — point-and-click, plain English Free tier available Handles millions of rows efficiently 100% local — data never leaves your computer

Data Cleaning Operations Available in Diwadi

Every operation works on CSV, Excel (.xlsx), and Parquet files without any setup or configuration.

Remove Duplicates

Most Used

Remove exact duplicate rows, or deduplicate by specific columns (e.g., keep one record per email address, even if other fields differ). Choose which record to keep — first occurrence, last, or based on a condition.

Filter Rows

Powerful

Keep only rows matching your conditions — filter by value, range, contains text, starts with, ends with, or regex pattern. Chain multiple conditions with AND/OR logic. Works on any column type.

Trim Whitespace

operations.items.2.tag

Remove leading and trailing spaces from all text columns in one click. Also removes non-breaking spaces and other invisible characters that cause matching failures.

Fix Text Casing

operations.items.3.tag

Standardize text to UPPERCASE, lowercase, Title Case, or Sentence case. Apply to all text columns or specific ones. Instantly resolves "New York" vs "new york" vs "NEW YORK" inconsistencies across entire columns.

Remove Empty Rows

operations.items.4.tag

Delete rows where any cell is blank, or rows where a specific key column (like email, ID, or name) is empty. Also removes fully blank rows inserted by export tools.

Search and Replace

Regex Support

Find and replace values across entire columns or the whole dataset. Supports plain text and regex patterns — useful for standardizing abbreviations ("NY" → "New York"), removing unwanted characters, or fixing systematic errors.

Extract and Reorder Columns

operations.items.6.tag

Select only the columns you need, reorder them, and rename headers — without touching the source data. Useful for creating standardized exports from raw data with 50+ columns.

Before and After: Real Data Cleaning Examples

Customer List — Before Cleaning

Raw export from CRM with 3 common issues

EmailFirst NameCityStatus
john.smith@acme.com john smith new york active
john.smith@acme.com John Smith New York Active
sarah.j@corp.com_ Sarah Jones BOSTON active
(empty) Mike Brown Chicago inactive
mike.b@firm.com mike brown chicago_ Inactive
  • Duplicate email (rows 1 & 2)
  • Inconsistent casing on names and cities
  • Trailing space in email (row 3)
  • Empty email field (row 4)
  • Duplicate customer (rows 4 & 5)

Customer List — After Cleaning

After deduplication, casing fix, trim, and empty row removal

EmailFirst NameCityStatus
john.smith@acme.com John Smith New York Active
sarah.j@corp.com Sarah Jones Boston Active
mike.b@firm.com Mike Brown Chicago Inactive
5 rows → 3 rows. Duplicates removed. Casing standardized. Whitespace trimmed. Empty records dropped.

Your Data Never Leaves Your Computer

Business data is sensitive — customer lists, sales figures, employee records, financial transactions. Many cloud-based data cleaning tools require you to upload your files to their servers. Diwadi is different.

100% Local Processing

Every cleaning operation happens on your computer using your CPU and memory. No data is transmitted over the internet at any point — not even anonymized metadata.

No Account Required

Download Diwadi and start cleaning immediately. No login, no account creation, no email verification. Your data cleaning activity is not tracked or logged anywhere.

GDPR and Data Compliance Friendly

If your data contains personal information (names, emails, phone numbers), keeping it local means you don't need to add a third-party processor to your data processing agreements.

Works Offline

Clean data on a plane, at a client site, or on a machine with no internet access. Diwadi requires no connectivity to function — ever.

How to Clean Your Data with Diwadi

1

Download and Open Diwadi

Install Diwadi on your Mac or Windows computer. Open the Data Tools section. No account or internet connection needed.

2

Load Your File

Drag and drop your CSV, Excel, or Parquet file into Diwadi. It previews the first rows instantly so you can see the structure and spot issues before cleaning.

3

Apply Cleaning Operations

Select the operations you need: remove duplicates, trim whitespace, fix casing, filter rows, or search and replace. Each operation shows a preview of what will change before you apply it.

4

Export the Cleaned File

Save the cleaned data as CSV, Excel, or Parquet. Your original file is unchanged — Diwadi always writes to a new file, so you can compare before and after.

Data Tools in Diwadi

Frequently Asked Questions

Can I clean data without knowing Python or SQL?

Yes — that is exactly what Diwadi is built for. Every cleaning operation is point-and-click: select the operation, pick your columns, apply. You do not write any code, formulas, or queries. Business analysts, operations teams, and Excel power users use Diwadi to do in minutes what previously required a data engineer to script.

How does Diwadi handle very large CSV files that crash Excel?

Excel struggles with files over 100,000–200,000 rows and often crashes or hangs on files with a million rows. Diwadi uses efficient streaming processing and can handle files with millions of rows without loading everything into memory at once. If your file is too large for Excel, Diwadi is designed precisely for that use case.

Can I remove duplicates based on specific columns rather than the entire row?

Yes. Diwadi lets you choose which columns to use for deduplication. For example, you can remove rows where the email column matches a previous row — even if the name or phone number is different. You can also choose whether to keep the first or last occurrence of a duplicate.

How is Diwadi different from OpenRefine for data cleaning?

OpenRefine is a powerful tool but has a steep learning curve — it runs as a local server accessed via a browser, uses its own query language (GREL), and requires familiarity with its facet-based workflow. Diwadi is designed for non-technical users with a straightforward interface: pick an operation, set parameters, apply. For common cleaning tasks like deduplication, casing fixes, and whitespace trimming, Diwadi is significantly faster to use.

Is Diwadi really free for data cleaning?

Diwadi has a generous free tier that covers the core data cleaning operations — removing duplicates, filtering rows, trimming whitespace, fixing casing, and search/replace. You can clean real business data without paying. Advanced features and higher volume usage have paid options.

Can Diwadi clean Excel files (.xlsx) directly, or only CSV?

Diwadi works directly with Excel (.xlsx) files, CSV, and Parquet format. You do not need to convert Excel to CSV before cleaning. You can also export the cleaned result in any of these formats — for example, clean an Excel file and export as CSV, or vice versa.

How do I standardize inconsistent date formats in a column?

Use Diwadi's search and replace with regex to normalize common date patterns. For example, you can convert "DD/MM/YYYY" and "MM-DD-YYYY" patterns to ISO 8601 format ("YYYY-MM-DD") using regex replacement rules. For complex date normalization, the filter and transform operations support pattern-based replacement across entire columns.

Does data cleaning in Diwadi modify my original file?

No. Diwadi always writes the cleaned data to a new output file. Your original CSV or Excel file is never modified. This means you can always compare the original and cleaned versions, and there is no risk of accidentally overwriting source data.

How much does Alteryx cost, and is Diwadi a real alternative?

Alteryx Designer starts at approximately $5,195 per user per year — it is enterprise software built for large data pipelines and BI teams. Diwadi is not a full replacement for Alteryx in enterprise ETL scenarios. However, for individual business analysts who need to clean and prepare data for reports, Diwadi covers the most common tasks (deduplication, filtering, casing, whitespace) at a fraction of the cost, with no coding required.

Can I chain multiple cleaning operations together?

Yes. You can apply multiple operations in sequence: first trim whitespace, then fix casing, then remove duplicates, then filter out rows where a column is empty. Each operation updates the preview so you see the cumulative result before exporting. This lets you build a cleaning workflow for your specific dataset without scripting.

Stop Cleaning Data by Hand

Diwadi handles duplicates, casing, whitespace, and filters — entirely on your computer. No uploads, no code, no expensive subscriptions.