Free Online Converter Tools — Instant, No Account
Convert units, numbers, timestamps, URLs, and encodings right in your browser. Results update as you type; tool code does not submit what you enter to a TOOLGRID processing endpoint.
Browser-local processingNo TOOLGRID input uploadNo account
Browse toolsPopular tasks
Start with a common task, then explore the rest of the suite.
Unit Converter→
Convert values between common length units.
Timestamp Converter→
Convert Unix timestamps and date strings instantly.
URL Encoder & Decoder — Convert Text to URL-Safe Format→
Encode text for URLs or decode encoded URL values.
JSON ↔ YAML Converter→
Convert between JSON and YAML using the standard js-yaml library — both directions, configurable indent, safe-by-default.
More tools
11 tools
CSV ↔ JSON Converter
Convert CSV to JSON (array of objects) or JSON to CSV — quoted-field aware, runs in your browser.
JSON to TypeScript Types
Generate TypeScript interfaces from a JSON sample — nested types, arrays, optional keys inferred.
Base Converter
Convert signed integers between bases 2, 8, 10, 16, 32, and 36 without precision loss.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 to text.
Query String Builder
Compose URL query strings from key-value rows — repeated keys for arrays, automatic percent-encoding, live preview.
URL Parser & Query String Decoder
Break any URL into protocol, host, path, query, and hash — UTM-labeled, double-encoding flagged, JSON output.
JWT Decoder & Verifier
Decode, build, and verify JWT tokens — entirely client-side (HS256).
What to know before you start
- Results as You Type
No submit button needed. Conversions update instantly so you can see the output while you work.
- Browser-Local Processing
Conversions run in your browser. Tool code does not submit entered text, files, or values to a TOOLGRID processing endpoint.
- No Account Gate
The current converters open without an account. Practical limits still depend on the browser, device, and input size.
- No Account Required
Open any tool and start converting immediately. No email or registration is required.
Frequently Asked Questions
Do I need to create an account to use these converters?
No account is required. Every tool on ToolGrid is accessible immediately without registration or login.
Are my inputs sent to a server?
Tool code processes conversions in your browser and does not submit what you type or paste to a TOOLGRID processing endpoint.
How accurate are the unit conversions?
Unit conversions use IEEE 754 double-precision arithmetic, which is accurate to 15–17 significant digits — sufficient for all practical engineering and everyday use.
What is Base64 encoding used for?
Base64 encodes binary data as printable ASCII characters. It is commonly used in email attachments, embedding images in CSS or HTML, and encoding API tokens and configuration values.
What is a Unix timestamp?
A Unix timestamp is the number of seconds (or milliseconds) elapsed since 00:00:00 UTC on 1 January 1970. It is the standard time format used in databases, APIs, and log files.
Can I use these tools offline?
Processing happens locally after the necessary page assets load, but TOOLGRID does not promise every converter is offline-ready. Only tools explicitly marked offline-ready make that claim.
Guides and workflow notes
How to convert units online
Open the Unit Converter, select the measurement type (length, weight, temperature, and more), enter a value in any field, and the result appears instantly in all other units. No submit button needed.
How to convert a Unix timestamp to a readable date
Paste a Unix timestamp (seconds or milliseconds) into the Timestamp Converter. The tool automatically detects the format and displays the equivalent UTC and local date-time. You can also convert a readable date back to a Unix timestamp.
How to encode or decode a URL
Open the URL Encoder & Decoder, paste the URL or component you want to encode, and the percent-encoded version appears immediately. Switch modes to decode an encoded string back to readable text. The mode toggle covers both encodeURI (whole URL) and encodeURIComponent (single value) semantics — picking the right one for your use case is the difference between a working URL and a broken one.
How to convert text to Base64 (and back)
Open the Base64 Encoder/Decoder and paste any text. The encoded and decoded views update side-by-side as you type. Toggle between standard Base64 (used by most APIs, HTTP Basic Auth, and email MIME) and URL-safe Base64url (used by JWTs and OAuth) — picking the wrong mode is the #1 reason "my Base64 won't decode" tickets exist.
How to parse and inspect a URL
Paste any URL into the URL Parser to break it apart into protocol, host, path, query string, and hash fragment. UTM and tracking parameters (utm_source, gclid, fbclid, msclkid, etc.) are auto-labeled, and double-encoded values (where %2520 appears in place of %20) are flagged with a warning — a common production bug most online parsers silently hide.
How to build a query string from parameters
Use the Query String Builder when you need to construct (not just inspect) a URL with parameters. Add key-value rows; repeated keys produce array-style parameters (tag=a&tag=b) that match what Express, Rails, and Spring expect by default. All values are percent-encoded automatically via URLSearchParams.