dot.tools

Measured conclusion: Deep-tested. L2 outcome: tools_ok.

28 developer utilities for LLMs: format, convert, encode, decode, generate and validate — JSON, YAML, XML, SQL, JWT, certificates, CIDR subnets, cron, hashes, UUIDs, passwords, QR codes and more. Stateless, fast, free.

Add to your agent

Copy this into your MCP client config:

{
  "mcpServers": {
    "dot.tools": {
      "url": "https://dot.tools/mcp",
      "transport": "streamable-http"
    }
  }
}

Measured tools (28)

• base64 read-only

  Encode and decode Base64 strings online. Supports UTF-8 text and binary data.

  Parameters:

  • mode (required) — string — Whether to encode raw text to Base64 or decode Base64 back to text.
  • input (required) — string — The raw text to encode, or the Base64 string to decode.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• case-converter read-only

  Convert case online: camelCase, PascalCase, snake_case, SCREAMING_SNAKE_CASE, kebab-case, Title Case and more. Smart acronym and digit splitting. Free, instant, no sign-up.

  Parameters:

  • text (required) — string — The text to convert, in any mix of camelCase, PascalCase, snake_case, kebab-case or plain words.
  • target (required) — string — Target case: camel (camelCase), pascal (PascalCase), snake (snake_case), screaming-snake (SCREAMING_SNAKE_CASE), kebab (kebab-case), lower (lower case), upper (UPPER CASE) or title (Title Case).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• color-converter read-only

  Convert color codes between HEX, RGB, HSL, HWB and OKLCH. CSS keyword and Tailwind v3 matching, WCAG contrast ratios. Free, instant, no sign-up.

  Parameters:

  • color (required) — string — Color in any sRGB notation: #rgb/#rgba/#rrggbb/#rrggbbaa, rgb()/rgba(), hsl()/hsla(), hwb() (comma or space/slash syntax), or a CSS color keyword. OKLCH input is not accepted (out-of-gamut mapping), but OKLCH output is always provided.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• contrast-checker read-only

  Check color contrast against WCAG 2.x AA and AAA thresholds. Live preview, exact ratio, and pass/fail for normal text, large text and UI components. Free, instant.

  Parameters:

  • foreground (required) — string — Foreground (text/icon) color. Opaque color as #rgb/#rrggbb, rgb(), hsl(), hwb() or a CSS keyword (e.g. rebeccapurple). Colors with alpha below 1 are rejected — WCAG contrast is defined for opaque colors only.
  • background (required) — string — Background color. Opaque color as #rgb/#rrggbb, rgb(), hsl(), hwb() or a CSS keyword (e.g. rebeccapurple). Colors with alpha below 1 are rejected — WCAG contrast is defined for opaque colors only.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• cron-parser read-only

  Parse cron expressions into plain English. See next run times, field-by-field breakdowns, and clear validation errors.

  Parameters:

  • expression (required) — string — A standard 5-field cron expression: minute hour day-of-month month day-of-week. Supports *, lists, ranges, steps, and month/weekday names.
  • count (required) — integer — How many upcoming execution times to compute (max 10).
  • from — string — ISO-8601 start time for the next-execution preview. Defaults to now. Computed in UTC.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• diff-checker read-only

  Compare two texts or JSON documents online and see every change highlighted line by line. Whitespace-insensitive and key-sorted JSON modes. Free and instant.

  Parameters:

  • mode (required) — string — Compare raw text line-by-line, or parse both sides as JSON first (semantic compare).
  • a (required) — string — Original (old) content.
  • b (required) — string — Changed (new) content.
  • ignoreWhitespace (required) — boolean — Ignore leading/trailing whitespace on each line when comparing (jsdiff ignoreWhitespace semantics).
  • sortKeys (required) — boolean — JSON mode only: recursively sort object keys before comparing, so pure key-order differences produce no diff. Arrays keep their order.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• csv-json read-only

  Convert CSV to JSON and JSON to CSV online. Handles quoted fields, Excel semicolon exports and ragged rows. Free, fast, no sign-up.

  Parameters:

  • mode (required) — string — Conversion direction: CSV to JSON, or JSON to CSV.
  • input (required) — string — The CSV or JSON text to convert (max 1 MB).
  • delimiter (required) — string — Field delimiter. "auto" sniffs the first 10 records when converting CSV to JSON, and resolves to a comma when converting JSON to CSV.
  • hasHeader (required) — boolean — CSV → JSON only: treat the first row as object keys. When false, rows convert to arrays of strings.
  • indent (required) — string — CSV → JSON only: number of spaces per indentation level in the JSON output.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• hash-calc read-only

  Calculate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes online. Hash text or files securely in your browser — nothing is uploaded.

  Parameters:

  • text (required) — string — The UTF-8 text to hash with all supported algorithms.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• html-entities read-only

  Encode and decode HTML entities online.

  Parameters:

  • text (required) — string — The text to entity-encode, or the entity-encoded string to decode.
  • mode (required) — string — Whether to encode plain text into HTML entities or decode entities back to text.
  • encodeNonAscii — boolean — Encode mode only: also escape non-ASCII characters as hexadecimal numeric references (e.g. 😀 becomes 😀).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• json-escape read-only

  Escape text for JSON strings and unescape JSON string contents online.

  Parameters:

  • text (required) — string — The raw text to escape, or the JSON-escaped string to unescape.
  • mode (required) — string — Whether to escape raw text for embedding in a JSON string or unescape a JSON string back to raw text.
  • includeQuotes — boolean — Escape mode only: include the surrounding double quotes in the output (default false).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• json-formatter read-only

  Format, beautify, minify, and validate JSON online. Custom indentation, key sorting, and precise error locations.

  Parameters:

  • mode (required) — string — Beautify with indentation, minify to a single line, or validate only.
  • input (required) — string — The JSON text to format, minify, or validate.
  • indent (required) — string — Indentation used when beautifying: 2 spaces, 4 spaces, or tabs.
  • sortKeys (required) — boolean — Sort object keys alphabetically (recursively) before output.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• json-schema read-only

  Validate JSON against a JSON Schema or generate a draft 2020-12 schema from sample data. Detailed error paths, format detection, free and browser-based.

  Parameters:

  • mode (required) — string — validate: check an instance against a schema. generate: infer a draft 2020-12 schema from a sample document.
  • instance (required) — string — The JSON document to validate (max 1 MB in validate mode) or to infer a schema from (max 5 MB in generate mode).
  • schema — string — Required in validate mode: the JSON Schema (draft 2020-12) as JSON text, max 1 MB. Local $refs only; remote refs are never fetched.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• json-to-typescript read-only

  Turn any JSON payload into TypeScript interfaces online. Merges array item shapes, marks missing keys optional and dedupes identical structures. Free, no sign-up.

  Parameters:

  • json (required) — string — The JSON document to generate TypeScript types for (max 5 MB).
  • rootName (required) — string — Name for the root interface or type alias. Sanitized to PascalCase and must form a valid TypeScript identifier.
  • exportKeyword (required) — boolean — Prefix every declaration with the export keyword.
  • optionalWhenMissing (required) — boolean — Mark fields missing from some array items as optional (?). When false, they stay required with undefined added to the type union.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• xml-formatter read-only

  Format, beautify, minify, and validate XML online. Proper indentation, clear error detection with line numbers.

  Parameters:

  • mode (required) — string — Beautify with indentation, minify to a single line, or validate only.
  • input (required) — string — The XML document to format, minify, or validate.
  • indent (required) — string — Indentation used when beautifying: 2 spaces, 4 spaces, or tabs.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• yaml-json read-only

  Convert YAML to JSON and JSON to YAML online. Bidirectional, validated conversion with error locations.

  Parameters:

  • mode (required) — string — Conversion direction: YAML to JSON, or JSON to YAML.
  • input (required) — string — The YAML or JSON text to convert.
  • indent (required) — string — Number of spaces per indentation level in the output.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• jwt-decoder read-only

  Decode and inspect JSON Web Tokens online. View header, payload, claims and expiry — with optional HMAC (HS256/384/512) signature verification.

  Parameters:

  • token (required) — string — The JSON Web Token to decode (header.payload.signature).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• certificate-decoder read-only

  Decode X.509 certificates and CSRs online: PEM, DER, multi-cert bundles, SANs, extensions, fingerprints, chain signature checks — free, runs locally.

  Parameters:

  • pem (required) — string — PEM text with one or more blocks (CERTIFICATE and CERTIFICATE REQUEST are parsed; PRIVATE KEY blocks are skipped with a warning; PKCS#7/CMS is rejected per block), or a single bare-base64 DER object. Mixed bundles and trailing garbage are tolerated with warnings. Maximum 16 blocks, 64KB decoded DER per block.
  • nowMs — number — Optional Unix epoch milliseconds used as 'now' for validity status and deltas. Omit for a clock-free response: no status fields are emitted at all.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• url-encode read-only

  Percent-encode and decode URLs and query strings online.

  Parameters:

  • mode (required) — string — Whether to percent-encode or percent-decode the input.
  • scope (required) — string — component encodes/decodes every reserved character (like encodeURIComponent); full preserves URL structure characters like / : ? & = # (like encodeURI).
  • input (required) — string — The text to encode, or the percent-encoded string to decode.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• url-parser read-only

  Parse any URL into protocol, auth, host, port, path, query params and fragment. Edit query parameters in a decoded table.

  Parameters:

  • url (required) — string — The absolute URL to parse, including protocol.
  • params — array — Optional replacement query parameters — when given, the URL is rebuilt with these and the result reflects the new URL.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• pwd-gen read-only

  Generate cryptographically secure passwords up to 128 characters. Custom character sets, ambiguous-character filter, strength meter.

  Parameters:

  • length (required) — integer — Password length (8–128 characters).
  • lowercase (required) — boolean — Include lowercase letters (a–z).
  • uppercase (required) — boolean — Include uppercase letters (A–Z).
  • digits (required) — boolean — Include digits (0–9).
  • symbols (required) — boolean — Include symbols (!@#$%^&*…).
  • excludeAmbiguous (required) — boolean — Exclude ambiguous characters (I, l, 1, O, 0).
  • count (required) — integer — How many passwords to generate (1–20).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• uuid-gen read-only

  Generate UUID v4, UUID v7 and ULIDs online. Bulk generation up to 1000 IDs, uppercase and hyphen options, instant copy.

  Parameters:

  • format (required) — string — The identifier format to generate.
  • count (required) — integer — How many IDs to generate (1–1000).
  • uppercase (required) — boolean — Uppercase the generated IDs.
  • hyphens (required) — boolean — Include hyphens in UUIDs (ignored for ULID).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• mock-data read-only

  Generate realistic mock data for testing: fake people, emails, addresses, companies, products, UUIDs and more. Export as JSON, CSV or SQL.

  Parameters:

  • rows (required) — integer — Number of records to generate.
  • fields (required) — array — Fields to include in each record, in column order.
  • format (required) — string — Export format.
  • tableName (required) — string — Target table name for SQL INSERT statements.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• sql-beautify read-only

  Format and beautify SQL queries online. Supports PostgreSQL, MySQL, SQLite, SQL Server and Oracle. Keyword casing and custom indentation.

  Parameters:

  • sql (required) — string — The SQL query or script to format.
  • dialect (required) — string — The SQL dialect to parse and format for.
  • keywordCase (required) — string — Letter case applied to SQL keywords.
  • indentSize (required) — integer — Number of spaces per indentation level.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• unix-timestamp read-only

  Convert unix timestamps to dates and dates to epoch seconds or milliseconds online. Live clock, timezone-aware output, free and fast.

  Parameters:

  • mode (required) — string — Conversion direction: unix timestamp to date, or date to unix timestamp.
  • input (required) — string — For unix-to-date: a unix timestamp (integer or fractional seconds). For date-to-unix: an ISO 8601 date string. Strings without a timezone offset are interpreted as UTC.
  • unit (required) — string — Unit of the input timestamp for unix-to-date. "auto" treats absolute values >= 1e12 as milliseconds, otherwise seconds. Ignored for date-to-unix.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• qr-generator read-only

  Create QR codes for links, WiFi networks, text and email online. Custom colors, error correction and margins. Download as SVG or PNG — free, no sign-up.

  Parameters:

  • payload (required) — string — The content to encode: URL, text, WIFI: payload, mailto: link, etc.
  • ecLevel (required) — string — Error correction level: L (7%), M (15%), Q (25%) or H (30%) damage tolerance. Higher levels hold less data.
  • margin (required) — integer — Quiet zone width in modules (0–16). The QR spec recommends at least 4.
  • foreground (required) — string — Hex color of the dark modules.
  • background (required) — string — Hex color of the light modules and quiet zone.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• chmod-calc read-only

  Convert chmod permissions between octal (755) and symbolic (rwxr-xr-x) online. Handles setuid, setgid and sticky bits — free and instant.

  Parameters:

  • octal — string — Octal permission value: 3 or 4 digits (0-7), optional leading zero. Examples: 755, 0644, 4755.
  • symbolic — string — Symbolic permission string: 9 characters (rwxrwxrwx with s/S/t/T substitutions), or a 10-character ls -l string with a leading file-type character.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• cidr-calculator read-only

  Calculate network, broadcast, subnet mask and host counts from CIDR notation, or summarize any IP range into minimal CIDR blocks. IPv4 + IPv6 — free.

  Parameters:

  • mode (required) — string — "cidr" analyzes one CIDR block (network, broadcast, masks, host counts). "range" summarizes an arbitrary start-end IP range into the minimal set of CIDR blocks.
  • end — string — Required when mode is "range". Last address of the range, same family as start and not smaller.
  • cidr — string — Required when mode is "cidr". IPv4 or IPv6 CIDR notation, e.g. "192.0.2.0/24" or "2001:db8::/32". IPv4 rejects leading zeros and short/hex forms; IPv6 accepts one "::" compression and embedded IPv4 tails.
  • start — string — Required when mode is "range". First address of the range, IPv4 or IPv6.
  • normalize — boolean — When false (default), a CIDR with host bits set (e.g. "10.0.0.1/8") fails with errorCode HOST_BITS_SET and a suggestion field carrying the network CIDR. When true, the address is masked to its network and the result has normalized=true.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• number-base read-only

  Convert numbers between binary, octal, decimal, hexadecimal and any base 2-36 online. Arbitrary precision, clear digit errors — free.

  Parameters:

  • value (required) — string — The number to convert, written in fromBase. Digits 0-9 and a-z (case-insensitive); optional leading - or + sign. 0x/0b/0o prefixes are accepted only when they match fromBase (16/2/8). Negative values convert sign-magnitude: the minus sign is carried to every output.
  • fromBase (required) — integer — The base the value is written in, 2-36.
  • toBase — integer — Optional extra base to convert into, returned as custom.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

Measured by MCPYP probing. Untested fields are omitted, never estimated. Listing is always free; MCPYP never proxies calls or stores user tokens.