Comma-Separated Values (.csv)

RFC Standardno

Comma-Separated Values (CSV) is a ubiquitous plain-text format for tabular data, where each line represents a data record and fields are separated by delimiter characters.

Pretvori XLSX u CSV

Besplatni XLSX u CSV pretvarač u pregledniku. Trenutno pretvorite datoteke na svom uređaju.

Komprimirajte CSV online

100% privatna kompresija u pregledniku – datoteke nikada ne napuštaju vaš uređaj

Pregledaj i metapodaci

Operativni sustavi i alati za analizu datoteka identificiraju CSV datoteke provjerom početnog niza binarnih bajtova:

Odaberite ili povucite datoteke

Odaberite ili ispustite datoteke ovdje

100% privatna pretvorba u pregledniku - datoteke nikada ne napuštaju vaš uređaj

ili zalijepi Ctrl+V
Jamstvo privatnosti nulte mrežne transmisije: 0 bajtova učitano na vanjske poslužitelje. Sva obrada odvijala se lokalno u sandčiću vašeg preglednika.

Potpis zaglavlja na razini bajtova (Magic Bytes)

Operativni sustavi i alati za analizu datoteka identificiraju CSV datoteke provjerom početnog niza binarnih bajtova:

HEX POTPIS (POMAK 0):

Plain Text

ASCII PRIKAZ: ASCII / UTF-8

Standardizacija: RFC 4180 / IETF

Tehničke specifikacije

Arhitektura spremnikaDelimited flat text file representing tabular data rows and columns
KompresijaGzip / Deflate achieves 85%-95% compression on repetitive tabular records
字节序UTF-8 text stream (optional UTF-8 BOM EF BB BF used by Excel)
Prostori bojaNot applicable
Kanali i strukturaRow records delimited by CRLF with columns delimited by commas
Maksimalne dimenzijeUnbounded; streamable to gigabytes without loading entire file in memory
ProzirnostNot applicable
Streaming i progresivnoNative line-by-line stream processing supported by all data pipelines

Tehnička matrica usporedbe: CSV vs Konkurencija

Tehnički atributCSV (Trenutno)Excel (XLSX)ParquetJSON
File TypePlain text flat tableZipped XML spreadsheetBinary columnar storageHierarchical text
Multiple SheetsNo (single flat table only)Yes (multiple workbooks and sheets)Partition-based storageNested arrays and objects
Data TypesUntyped raw textTyped cells, formulas, formattingStrict binary column typesPrimitive types (string, number, bool)
Big Data AnalyticsSlow (requires reading every row linearly)Not suitable for big dataUltra-fast (column pruning & predicate pushdown)Moderate

Uobičajeni načini oštećenja i vodič za heksadecimalni oporavak

⚠️ Columns shift to the right or row counts do not match.

Temeljni uzrok: A text field containing an unescaped comma without surrounding quotation marks.

Oporavak: RFC 4180 requires fields containing commas to be wrapped in double quotes: "Smith, John".

⚠️ Accented characters render as strange symbols (mojibake like é instead of é) in Excel.

Temeljni uzrok: Excel opened a UTF-8 CSV assuming the legacy Windows ANSI/CP1252 character encoding.

Oporavak: Prepend the 3-byte UTF-8 Byte Order Mark (0xEF 0xBB 0xBF) to the beginning of the file.

Sigurnosna analiza i vektori napada na parser

CSV files open directly in spreadsheet software like Excel and Google Sheets, exposing users to Formula Injection (CSV Injection) attacks.

Poznati vektori napada

  • Formula Injection: Cells starting with '=', '+', '-', or '@' executing spreadsheet macros or DDE commands (e.g. '=cmd|' /C calc'!A0').
  • Data exfiltration via HYPERLINK() formulas sending sensitive cell data to remote attacker servers upon click.

Najbolje obrambene prakse: When exporting user data to CSV, prepend a single quote (') or tab to any cell starting with '=', '+', '-', or '@' to force plain text rendering in Excel.

Povijesni izvori i prekretnice

2005IETF publishes RFC 4180, establishing the formal specification for CSV files.
1972IBM Fortran (H Extended) compiler implements comma-delimited input/output.

Ključne prednosti

  • Maximum simplicity: readable in any text editor and importable into every database and spreadsheet.
  • Extremely fast line-by-line streaming without building a full in-memory DOM.
  • Minimal overhead: no verbose tag syntax or schema definitions.

Tehnička ograničenja i nedostaci

  • No standard data types: numbers, dates, booleans, and text are all stored as raw strings.
  • No support for multiple sheets, cell formatting, formulas, or metadata.
  • Delimiter conflicts (commas inside text, decimal commas in European locales) cause frequent parsing bugs.

Zanimljive tehničke činjenice

  • In many European countries where commas are used as decimal points, semicolons (;) are used instead of commas as CSV separators.
  • Microsoft Excel historically required a UTF-8 BOM (0xEF 0xBB 0xBF) to correctly display non-ASCII accented characters.

Često postavljana tehnička pitanja

What is RFC 4180?

RFC 4180 is the official IETF standard for CSV. It mandates that fields containing commas, line breaks, or double quotes must be enclosed in double quotes, and internal quotes must be escaped by doubling them ("").

Why do CSV files open with corrupted characters in Excel?

Older versions of Microsoft Excel default to the local Windows code page (like Windows-1252) rather than UTF-8 when opening CSV files directly. Adding a UTF-8 BOM (Byte Order Mark) at the start of the file forces Excel to decode UTF-8 correctly.