Free Online Converters
Conversion problems look trivial until you hit the edge cases. Turning JSON into CSV is easy when the data is flat — and a minefield when objects nest three levels deep. Converting a cup of flour to grams is easy — until you realize a cup of flour and a cup of sugar weigh very different amounts. A good converter is not the one that does the obvious arithmetic; it is the one that handles the decisions hiding underneath, and shows its work so you can verify the result. That is the standard every tool on this page is built to.
The data format converters move structured data between the formats developers and analysts actually trade in. JSON to CSV flattens nested objects into dot-notation columns instead of silently dropping them. XML to JSON makes explicit choices about attributes and repeated elements — the two places where naive converters mangle data. YAML to JSON handles multi-document files and reports parse errors with line numbers, so a bad indent does not cost you ten minutes of squinting. Each converter works in both directions, because round-tripping is half the job.
The web and education converters serve narrower but constant needs: px to rem honors whatever root font size your project uses rather than assuming 16px, and the GPA to percentage converter applies the standard US 4.0-scale letter-grade mapping with a full table so you can sanity-check any single value. The kitchen converter is per-ingredient by design — cups measure volume, grams measure weight, and the density of the ingredient is what links them, so a one-size-fits-all multiplier would simply be wrong.
The last four converters are deliberately specific to one audience: people dealing with Indian gold weights, land records, and number notation. The tola (11.6638 grams) is still the everyday unit for gold across South Asia. Land in India is recorded in units like bigha and gaj, and the bigha varies by state — a bigha in Uttar Pradesh is not a bigha in Rajasthan, which is why that converter is state-aware. The lakh/crore converter bridges the Indian and international numbering systems for anyone reading Indian financial figures or sending money home. All of these conversions, like everything else here, happen on your own device — no uploads, no signup, and your numbers and files stay private.
Data formats
Move structured data between JSON, CSV, XML, and YAML with the nesting, attribute, and error handling done right.
JSON ⇄ CSV Converter
Convert JSON to CSV and CSV to JSON in your browser — nested objects flattened to dot-notation columns, delimiter options, and file download.
XML ⇄ JSON Converter
Convert XML to JSON and JSON back to XML in your browser — attribute handling, repeated elements as arrays, and clear parse error messages.
YAML ⇄ JSON Converter
Convert YAML to JSON and JSON to YAML instantly in your browser — multi-document support, error line numbers, and copy or download output.
Web & education
Convert CSS units with any root font size and translate US 4.0-scale GPAs to percentages.
PX ⇄ REM Converter
Convert px to rem and rem to px instantly with any root font size — plus a full conversion table and CSS tips for accessible font sizing.
GPA to Percentage Converter
Convert a 4.0-scale GPA to a percentage and back, with the standard US letter-grade mapping (A = 4.0). Includes a full conversion table.
Kitchen
Convert recipe volumes to weights with per-ingredient accuracy for flour, sugar, butter, and dozens more.
South Asian units
Converters for Indian gold weights, land records, and number notation — tola, bigha, gaj, and lakh/crore.
Lakh/Crore ⇄ Million/Billion Converter
Convert lakh and crore to million and billion instantly — both directions, with Indian and international comma formatting and words output.
Indian Land Unit Converter (Bigha/Katha/Guntha)
Convert bigha to acre, square feet, and hectare with state-accurate values for UP, Bihar, Rajasthan, and Bengal — plus katha, guntha, and marla.
Gaj ⇄ Square Feet Converter
Convert gaj to square feet and square feet to gaj — 1 gaj = 9 sq ft — with plot-size tables for 50, 100, and 200 gaj and square yard equivalents.
Tola ⇄ Gram Converter (Gold Weight)
Convert tola to grams and back — 1 tola = 11.6638 g, the standard South Asian gold weight — with ratti, masha, troy ounce, and kilogram conversions.
Guides
JSON vs. CSV vs. XML vs. YAML: Which Data Format to Use
CSV for tables, JSON for APIs, YAML for config, XML for documents. Learn each format's strengths and what gets lost when you convert between them.
px vs. rem vs. em: Which CSS Unit to Use and When
rem scales with the root, em with the parent, px is fixed. Learn which CSS unit to use for accessible, predictable sizing — and how to convert between them.
Frequently asked questions
How accurate are these converters, and how is rounding handled?
Unit converters use the standard published conversion factors (for example, 1 tola = 11.6638 g and 1 gaj = 9 sq ft) and compute at full precision before rounding the display. Where a conversion is inherently approximate — like cups to grams, which depends on ingredient density and how the ingredient is packed — the tool says so rather than presenting a false-precision number.
Does converting JSON to CSV lose information?
It can, because CSV is a flat format and JSON is not. This converter minimizes the loss by flattening nested objects into dot-notation columns instead of discarding them, but deeply nested arrays may still need restructuring. Converting in the other direction, CSV to JSON, is lossless. If you need a faithful round-trip, check the output before depending on it.
Why does this site have converters for tola, bigha, gaj, and lakh/crore?
Those four tools exist for a specific audience: people handling Indian gold weights, land records, and number notation. If you are pricing family gold in tola, reading a property deed measured in bigha or gaj, or translating a crore figure from Indian financial news into millions, these converters do the exact math — including the state-by-state variation in the bigha.
Why does the bigha converter ask which state the land is in?
Because the bigha is not a standardized unit. Its size differs significantly between Indian states — Uttar Pradesh, Bihar, Rajasthan, and West Bengal each use different values — so a correct acreage depends on knowing which state's bigha the record uses. The converter applies state-accurate values rather than a single misleading average.
Why do cups to grams conversions change depending on the ingredient?
Cups measure volume and grams measure weight, so the conversion runs through density. A cup of all-purpose flour weighs much less than a cup of granulated sugar, which weighs less than a cup of honey. That is why the converter asks for the ingredient first — a universal cups-to-grams number does not exist.
Are my files and data uploaded when I convert them?
No. Parsing and conversion run as JavaScript in your browser, so JSON exports, config files, and any numbers you type stay on your machine. You can convert proprietary or sensitive data without it ever crossing the network, and no account is required.