Free online developer tools

502 tools

Small utilities developers reach for daily: JSON and YAML formatters, Base64 and URL encoders, regex testers, JWT decoders, diff viewers and cron helpers. Prefer tools marked as running in your browser when you paste tokens, keys or production data, because nothing is uploaded.

Showing 97–120 of 502

0.647score
Screenshot to HTML
HuggingFaceM4
Upload a screenshot of a web page and get HTML that approximates it.
ArtifactAINo sign-up★ 934developer tools
0.629score
Tools
mydearcc
A toolbox of free online utilities including CSS minify, JSON format, encryption, QR codes and image tools.
Artifact★ 376developer tools
0.625score
Convert to ONNX
onnx-community
Converts a Hugging Face model to the ONNX format.
ArtifactAI★ 195developer tools
0.624score
Qwen3 Coder WebDev
Qwen
Describe a web page or small app and Qwen3-Coder writes the HTML, with a live preview.
ArtifactAINo sign-up★ 1.2Kdeveloper tools
0.622score
Tools
jaywcjlove
A collection of online utilities for web developers and programmers, hosted as one tool site.
Artifact★ 274developer tools
0.622score
Html Tools
justhtmls
An open-source set of lightweight HTML tools that run in the browser with no install and keep data private.
Artifact★ 268developer tools
0.621score
Qwen2.5 Coder Artifacts
sambanovasystems
Describe a small app and get generated code that previews in the page.
ArtifactAINo sign-up★ 276developer tools
0.621score
Convert to Safetensors
safetensors
Converts PyTorch model weights to the safetensors format; asks for a Hugging Face token.
ArtifactNo sign-up★ 270developer tools
0.619score
Code Llama Playground
codellama
Generate and complete code by typing a prompt into the Code Llama playground.
ArtifactAINo sign-up★ 251developer tools
0.616score
Chat Template Playground
huggingfacejs
Edit a Jinja chat template and preview how it formats a conversation into model input text.
ArtifactNo sign-up★ 221developer tools
0.613score
MLX My Repo
mlx-community
Converts a Hugging Face model to Apple MLX format and uploads it to your account; needs login.
Artifact★ 220developer tools
0.611score
Html Tools
chicogong
A toolbox of over 1,000 single-file HTML tools that run in the browser, work offline and keep data local.
Artifact★ 161developer tools
0.608score
It Toolbox
Zoroaaa
Online developer toolbox with 146 tools for formatting, encoding, hashing, network lookups, text processing and colors.
Artifact★ 142developer tools
0.606score
Text Forge
seehiong
Toolbox with text processing, code formatting, regex testing, encoding, hashing and other web utilities.
Artifact★ 129developer tools
0.606score
GraphiQL Online
Lucas Constantino
Hosted GraphiQL that connects to any GraphQL endpoint URL you supply.
ArtifactNo sign-up★ 70developer tools
0.603score
JMESPath
JMESPath
Try JMESPath expressions against JSON in an interactive tutorial and tester.
ArtifactNo sign-up★ 62developer tools
0.602score
Agent Architecture
TheJacksonCode
A visual designer for laying out multi-agent systems for Claude Code.
ArtifactAI★ 110developer tools
0.596score
Nano ID Collision Calculator
zelark
Estimates collision odds for Nano ID given alphabet size, id length and generation speed.
ArtifactNo sign-up★ 44developer tools
0.593score
Json Viewer
uiwjs
Paste JSON to beautify it, pretty print it and explore it as a collapsible tree.
Artifact★ 60developer tools
0.590score
Auto-Detect Decoder
curtyo18
Auto-detects pasted strings such as JWT, JSON, base64, URI, timestamp or gzip and shows the decoded view.
ArtifactNo sign-upIn-browserdeveloper tools
0.590score
Cron Expression Explainer
curtyo18
Explains a cron expression in plain words, field by field, and lists the next ten run times.
ArtifactNo sign-upIn-browserdeveloper tools
0.590score
CSS Inliner for Email
Jam.dev
Moves the CSS you paste into inline style attributes on the HTML, the format email clients expect.
ArtifactNo sign-upIn-browserdeveloper tools
0.590score
CSS Units Converter
Jam.dev
Converts CSS pixel values to rem and back.
ArtifactNo sign-upIn-browserdeveloper tools
0.590score
ENV to netlify.toml
Jam.dev
Rewrites the variables of a .env file as entries for a netlify.toml configuration.
ArtifactNo sign-upIn-browserdeveloper tools