lardr.dev changelog https://lardr.dev/changelog/ Free developer tools that run in your browser: encoders, converters, hashes, formatters, and explainers for algorithms and AI models. Nothing is uploaded. en Step through algorithms; HTTP headers; Base64 jobs https://lardr.dev/web/http-headers/ lardr-2026-09-27-39 Sun, 27 Sep 2026 12:00:00 GMT Sorting and pathfinding now have Play, Pause and Step, with a sentence for every move. A new HTTP header lookup explains any header, or a whole pasted block. Common Base64 jobs, like a Basic auth header, have their own pages. New: algorithm pages, positional encoding and quantization https://lardr.dev/algorithms/ lardr-2026-09-27-38 Sun, 27 Sep 2026 12:00:00 GMT Each algorithm (A*, Dijkstra, quicksort, merge sort and more) has its own page with the visualizer set to it. New AI tools show the sine waves transformers add to positions, and what int8 and int4 do to model weights. New: graph algorithms visualizer https://lardr.dev/algorithms/graph-algorithms/ lardr-2026-09-27-37 Sun, 27 Sep 2026 12:00:00 GMT Type an edge list like "A B 4" and get shortest paths, breadth-first and depth-first order, a topological sort, a minimum spanning tree or components, drawn with the result highlighted. New: sorting algorithm visualizer https://lardr.dev/algorithms/sorting/ lardr-2026-09-27-36 Sun, 27 Sep 2026 12:00:00 GMT Watch quicksort, merge sort, heapsort, shellsort, insertion, selection and bubble sort sort your numbers, see how many comparisons each makes, and race two side by side. New category: Algorithms, starting with a pathfinding visualizer https://lardr.dev/algorithms/pathfinding/ lardr-2026-09-27-35 Sun, 27 Sep 2026 12:00:00 GMT Draw walls or make a maze, then watch A*, Dijkstra, breadth-first, greedy and depth-first search find the way. Race two side by side, and share a maze as a link. Keyboard shortcuts, copy from the paste box https://lardr.dev/ lardr-2026-09-27-34 Sun, 27 Sep 2026 12:00:00 GMT Press ? for the keyboard shortcuts. The paste box can copy a result without opening the tool, and several tools now open with a worked example. JSON diff shows changes in the document https://lardr.dev/convert/json-diff/ lardr-2026-09-26-33 Sat, 26 Sep 2026 12:00:00 GMT JSON Diff now shows the whole document with removed lines in red and added lines in green, and folds long unchanged parts. Password fields have the eye inside the field, and dropdowns are tidier. New: bcrypt hash generator and checker https://lardr.dev/hash/bcrypt/ lardr-2026-09-26-32 Sat, 26 Sep 2026 12:00:00 GMT Hash a password with bcrypt at any cost from 4 to 14, or check a password against a bcrypt hash. The password stays hidden until you press Show. Unit converter: volume, area, speed and time https://lardr.dev/number/unit-converter/ lardr-2026-09-26-31 Sat, 26 Sep 2026 12:00:00 GMT Convert gallons, cups, acres, hectares, km/h, mph, knots, minutes and more. New pages for common pairs like liters to gallons and mph to km/h. Passwords and keys are hidden until you choose to show them https://lardr.dev/hash/password-generator/ lardr-2026-09-26-30 Sat, 26 Sep 2026 12:00:00 GMT Wi-Fi passwords, generated passwords, HMAC keys and JWT secrets now show as dots, with an eye button to reveal them. Copy and download still use the real value. New: color palette generator and semver range pages https://lardr.dev/number/color-palette/ lardr-2026-09-26-29 Sat, 26 Sep 2026 12:00:00 GMT Pick one color and get complementary, analogous, triadic and other schemes, with swatches to copy. Common npm range forms like ^ and ~ now have their own pages. New: attention calculator https://lardr.dev/ai/attention-calculator/ lardr-2026-09-26-28 Sat, 26 Sep 2026 12:00:00 GMT Type small Q, K and V matrices and see each step of transformer attention: scaled scores, softmax weights, an optional causal mask, and the output. Wi-Fi QR codes you can print https://lardr.dev/encode/qr-code/ lardr-2026-09-26-27 Sat, 26 Sep 2026 12:00:00 GMT The QR code generator can now build a Wi-Fi login from the network name and password. Print puts the code and the password on one page for guests. Paste anything also recognises XML, HTML and TOML. New: JSON to Go struct https://lardr.dev/convert/json-to-go/ lardr-2026-09-26-26 Sat, 26 Sep 2026 12:00:00 GMT Paste JSON and get Go structs with json tags, Go initialisms like ID and URL, and omitempty for keys that are not always there. New: QR code generator and Markdown to HTML https://lardr.dev/encode/qr-code/ lardr-2026-09-26-25 Sat, 26 Sep 2026 12:00:00 GMT Turn a link or any text into a QR code and download it as SVG or PNG. Preview Markdown as you type and copy safe HTML, with tables and task lists. New: YAML formatter and HTML formatter https://lardr.dev/convert/yaml-formatter/ lardr-2026-09-26-24 Sat, 26 Sep 2026 12:00:00 GMT Check YAML for indentation errors and duplicate keys, and tidy it without losing comments. Beautify or safely minify HTML, with pre, script and style left untouched. New: JSON to XML and TOML to JSON converters https://lardr.dev/convert/toml-to-json/ lardr-2026-09-26-23 Sat, 26 Sep 2026 12:00:00 GMT Convert JSON and XML both ways, with attributes and repeated elements handled. Convert TOML and JSON both ways, keeping big integers and dates. New: XML formatter and ROT13 / Caesar cipher https://lardr.dev/web/xml-formatter/ lardr-2026-09-26-22 Sat, 26 Sep 2026 12:00:00 GMT Format, minify and check XML, with the line and column of any error. Shift text by 13 or any amount, or list all 25 shifts to crack a Caesar cipher. New: JSON diff and Morse code translator https://lardr.dev/convert/json-diff/ lardr-2026-09-26-21 Sat, 26 Sep 2026 12:00:00 GMT Compare two JSON documents by path, ignoring key order and formatting. Translate text to Morse code and back, and play it as sound. New: cosine similarity, two's complement, notable float values https://lardr.dev/ai/cosine-similarity/ lardr-2026-09-26-20 Sat, 26 Sep 2026 12:00:00 GMT Compare vectors and embeddings by cosine similarity. The base converter can show 8 to 64-bit two's complement. Values like 0.1, MAX_SAFE_INTEGER and NaN have their own float pages. New: softmax and cross-entropy calculator, chmod mode pages https://lardr.dev/ai/softmax-calculator/ lardr-2026-09-26-19 Sat, 26 Sep 2026 12:00:00 GMT Turn scores into probabilities and see the loss and perplexity for the right answer. Common chmod modes like 755 and 600 now have their own pages, and paste anything recognises permissions and version ranges. New: chmod calculator, semver checker and float inspector https://lardr.dev/number/float-inspector/ lardr-2026-09-26-18 Sat, 26 Sep 2026 12:00:00 GMT Turn 755 into rwxr-xr-x with a grid of boxes. See what ^1.2.3 allows and test versions against it. See the exact value a float stores and why 0.1 + 0.2 is not 0.3. New: RTK output visualizer https://lardr.dev/ai/rtk-visualizer/ lardr-2026-09-26-17 Sat, 26 Sep 2026 12:00:00 GMT Paste git, ls, grep or test output and see it shortened the way rtk does for AI agents, with token counts before and after. Plainer words, clearer buttons https://lardr.dev/ lardr-2026-09-26-16 Sat, 26 Sep 2026 12:00:00 GMT Every tool now answers common questions on the page in short, plain English. Buttons show an icon with their word, and the password generator has a Regenerate button. New: AI tools: token counter, sampling explorer, memory calculator https://lardr.dev/ai/ lardr-2026-09-26-15 Sat, 26 Sep 2026 12:00:00 GMT Count tokens with the real GPT-4o and GPT-4 tokenizers and see every split; watch temperature, top-k and top-p reshape a next-token choice; and work out how much GPU memory a model needs. Paste anything shows the answer first https://lardr.dev/ lardr-2026-09-26-14 Sat, 26 Sep 2026 12:00:00 GMT Each suggestion now previews the result before you open it, offers every way forward, and recognises CSV, YAML, status codes, hashes and measurements too. Search can open a tool in the right direction https://lardr.dev/ lardr-2026-09-25-13 Fri, 25 Sep 2026 12:00:00 GMT Type "base64 decode" or "timestamp to date" and the result opens the tool already set that way. Pin tools, and tools remember how you left them https://lardr.dev/ lardr-2026-09-25-12 Fri, 25 Sep 2026 12:00:00 GMT Pin a tool to show it first on the home page. Each tool also reopens with the direction and options you last chose. Cron builder and time zones https://lardr.dev/web/cron-parser/ lardr-2026-09-25-11 Fri, 25 Sep 2026 12:00:00 GMT Build a cron expression from five menus, and see the next runs in the time zone your scheduler uses, daylight saving included. Diff: ignore whitespace and case, compare JSON by content https://lardr.dev/text/text-diff/ lardr-2026-09-25-10 Fri, 25 Sep 2026 12:00:00 GMT Two JSON documents with keys in a different order now show no differences, and line diffs get a side-by-side view. Inspect a UUID https://lardr.dev/hash/uuid-generator/ lardr-2026-09-25-9 Fri, 25 Sep 2026 12:00:00 GMT Paste a UUID into the UUID Generator to see its version, variant and, for v1, v6 and v7, when it was made. Works offline https://lardr.dev/privacy/ lardr-2026-09-25-8 Fri, 25 Sep 2026 12:00:00 GMT Any tool you have opened keeps working with the network off. It is also the simplest proof that nothing you type is uploaded. Regex pattern library, unit pairs and cron schedules https://lardr.dev/text/regex-tester/ lardr-2026-09-25-7 Fri, 25 Sep 2026 12:00:00 GMT Thirty common regular expressions, thirty-six unit conversions and thirty-nine cron schedules, each a pre-filled working tool. Regex explained, token by token, and exported as code https://lardr.dev/text/regex-tester/ lardr-2026-09-25-6 Fri, 25 Sep 2026 12:00:00 GMT The regex tester explains each part of a pattern and gives it back as JavaScript, Python or Go. Timestamps in logs, JWT expiry in words, URL query editing https://lardr.dev/number/timestamp-converter/ lardr-2026-09-25-5 Fri, 25 Sep 2026 12:00:00 GMT Paste a log to convert every timestamp in it; JWTs say "expired 3 days ago" and warn about weak secrets; URLs split into an editable query table. Hash files and check checksums https://lardr.dev/hash/sha256/ lardr-2026-09-25-4 Fri, 25 Sep 2026 12:00:00 GMT Drop a file on any hash tool to hash it, of any size, and paste the published checksum to see whether it matches. Base64 images and files https://lardr.dev/encode/base64/ lardr-2026-09-25-3 Fri, 25 Sep 2026 12:00:00 GMT Base64 that decodes to an image or a file now shows a preview and a download instead of garbled text. The JSON formatter fixes near-JSON https://lardr.dev/convert/json-formatter/ lardr-2026-09-25-2 Fri, 25 Sep 2026 12:00:00 GMT Trailing commas, comments, single quotes, unquoted keys and Python True/None are fixed automatically, and it tells you what it changed. Paste anything https://lardr.dev/ lardr-2026-09-25-1 Fri, 25 Sep 2026 12:00:00 GMT Paste into the box on the home page and it works out what you have (a JWT, JSON, a timestamp…) and opens the right tool. Tools also suggest a better one when you are in the wrong place.