Validate

Locate empty cells and NULL values across every column

Audit CSV columns for empty, null, and whitespace-only cells and produce a completeness report.

🛡️ Your rows never leave your browser.
Why Onfyt: Treats 'null', 'N/A', '-', 'none', and bare whitespace as missing—catching semantic blanks, not just empty strings.

Interactive Sample Data

idnameemailphone
1Grace Kerubograce@corp.com+254712345678
2Peter Njoroge+254722000001
3mercy@corp.com

How this tool works

Machine learning pipelines, CRM imports, and data warehouse ETL jobs fail or produce biased models when input data contains unexpected blanks. A missing-value audit answers the question: 'which columns are incomplete, and how incomplete?' before you commit to a cleaning strategy. DataFix produces two outputs: a per-column completeness report (filled/blank count and percentage) and an annotated version of your CSV with a `_has_missing` flag column and a `_missing_cols` column listing which fields are blank on each row. Incomplete datasets with blank cells, null literals, or undefined tokens degrade machine learning model training and cause null-pointer exceptions in backend processing services. Finding missing values involves scanning every column for empty strings, whitespace-only entries, null markers (such as "NULL", "N/A", "NaN", or "-"), and irregular sentinels. DataFix produces a comprehensive data quality heatmap showing missing value percentages and row indices across every column, helping analytics teams identify systemic upstream data collection failures before feeding data into reporting dashboards. Missing values represent critical data quality vulnerabilities in reporting dashboards and machine learning pipelines. Unchecked nulls trigger null-pointer exceptions in microservices and skew statistical averages. Identifying empty cells, sentinel tokens ('N/A', 'NULL', 'None'), and whitespace-only entries allows data engineers to remediate incomplete rows before ingestion.

Things that usually go wrong

  • Values like 'N/A', 'null', or 'None' are treated as strings, not as nulls — the tool reports on empty cells only unless you configure extra null tokens.
  • Cells containing only whitespace are counted as empty.

Edge cases we tested

🧪 Cell containing only spaces (' ')

Flagged as missing when 'treat whitespace as blank' is enabled.

🧪 Cell containing 'N/A' or 'NULL' string

Flagged as semantic null when null-synonym detection is on.

🧪 Column with 0% completeness (all blanks)

Highlighted in red in the report; flagged as a candidate for column removal.

Frequently Asked Questions

What counts as a missing value?

Empty string, whitespace-only, and standard null representations: null, NULL, N/A, NA, None, -, #N/A.

Can I see which rows are affected?

Yes — the tool adds a 'missing_columns' column listing which fields are empty for that row.

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