Your API is the front door to your app's data. If the door has a weak lock, it does not matter how good the rest of the app looks. These API security best practices give you a checklist you can apply to any app, whether you code it by hand or build it with the Base44 AI app builder.
Each practice below explains what to do, why it matters, and how it shows up when you build with Base44. For the wider picture, start with our guide to application security best practices.
TL;DR
API security means making sure only the right people and systems can call your API, and only for the data they are allowed to touch.
The ten practices below cover the controls that stop most real-world API breaches: encrypted traffic, strong authentication, per-record authorization, input validation, rate limiting, safe secrets, least privilege, logging, an up-to-date inventory and regular testing.
API security best practices at a glance
| Practice | What it stops |
|---|---|
| 01. Encrypt traffic with HTTPS | Eavesdropping and tampering |
| 02. Use strong authentication | Anonymous or impersonated callers |
| 03. Authorize every object | Users reading other users' records |
| 04. Validate all input | Injection and malformed data |
| 05. Rate limit requests | Abuse, scraping and brute force |
| 06. Protect secrets | Leaked keys and tokens |
| 07. Apply least privilege | Oversized blast radius |
| 08. Log and monitor | Attacks that go unnoticed |
| 09. Keep an API inventory | Forgotten, unpatched endpoints |
| 10. Test regularly | Gaps that ship to production |
Table 1.The ten practices and the risk each one reduces.
OWASP API Security Top 10Checked 3 nov 2026
01. Encrypt all traffic with HTTPS
Send every API call over HTTPS, and redirect or reject plain HTTP. Without encryption, anyone on the same network can read or change requests in transit, including tokens and personal data.
Apps published on Base44 are served over a secure connection by default, so your main job is to avoid sending sensitive values in URLs, where they end up in logs and browser history. Put them in headers or the request body instead.
02. Use strong authentication
Authentication answers "who is calling?". Require it on every endpoint that is not meant to be public, and prefer proven standards such as OAuth 2.0 or short-lived tokens over home-made schemes. Expire tokens, rotate them, and never accept credentials in query strings.
Base44 sets up authentication for your app so you do not have to design login from scratch. Decide up front which pages and actions need a signed-in user, and which are public on purpose.
03. Authorize every object, not just every endpoint
Authorization answers "what is this caller allowed to see or change?". The most common API flaw is broken object-level authorization: a signed-in user changes an ID in a request and reads someone else's record. Check ownership or role on the server for every record, every time.
Broken Access Control is the #1 web application security risk in OWASP Top 10:2025, found in 3.73% of applications tested across 2.8 million apps and 589 CWEs analyzed.
Logged in is not the same as allowed
Hiding a button in the UI does not protect the data behind it. Enforce access rules where the data lives, not only where it is displayed.
Who can view, edit or delete which records is a business question, and the answer shapes your whole data model. Design your roles and permissions before you build your entities. Retrofitting a permission model into an app built without one is significantly more work than starting with it.
04. Validate and sanitize all input
Treat every value that arrives at your API as untrusted. Check type, length, format and allowed values, reject anything unexpected, and never pass raw input into database queries or shell commands. This is your main defense against injection attacks.
When the AI generates your app, it gives you a working starting point rather than a finished product. Add field validation and edge-case handling for your own business rules, such as maximum quantities, allowed statuses or required formats.
05. Rate limit and throttle requests
Without limits, one caller can scrape your whole dataset, guess passwords or overload your service. Set a sensible number of requests per caller per minute, return a clear error when it is exceeded, and apply tighter limits to login and password-reset endpoints.
Start with limits that real users will never hit, then tighten them as you learn your normal traffic.
06. Protect your secrets
API keys, tokens and passwords do not belong in source code, screenshots, chat messages or public repositories. Store them as environment secrets, give each environment its own keys, and rotate any key you suspect has leaked.
With Base44 connectors, you plug in services such as Google Drive or Salesforce without pasting credentials into your app's pages. Keep any extra keys in your app's secrets settings, not in your prompts.
07. Apply the principle of least privilege
Give every user, service and key only the access it needs for its job, and nothing more. A read-only dashboard should not hold a key that can delete data. If a credential leaks, least privilege limits the damage. Our guide to the principle of least privilege goes deeper.
08. Log and monitor API activity
You cannot respond to what you cannot see. Record who called which endpoint, when, and with what result, but never write passwords, tokens or full personal data into logs. Alert on patterns such as repeated failed logins, sudden spikes or access from unexpected places.
For apps in a workspace, Security Center gives you one place to see, scan and act on the security of every app.
09. Keep an inventory of your APIs
Forgotten endpoints, old versions and test routes are easy targets because nobody patches them. Keep a list of every API you run, who owns it, which version is live, and what data it exposes. Retire old versions on a schedule and remove anything that is no longer used.
10. Test your API security regularly
Test before you ship and after every meaningful change. Try the attacks yourself: call endpoints without a token, swap record IDs between two test users, send oversized and malformed input, and exceed your rate limits. Fix what breaks, then repeat. Many teams skip this step: only 33% of organizations have a formal process to test AI-generated code for security vulnerabilities before deploying it to production, according to the Stack Overflow 2025 Developer Survey. Our list of common app security mistakes is a good source of test cases, and our guide on how to secure an app covers the wider routine.
Expert view
Security Scan is the one most builders forget about. It catches the gaps you wouldn't think to check.
Rotem Eisenkot
Product Manager at Base44
API security checklist before you launch
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API security best practices FAQ
API security is the set of practices that protect an API from unauthorized access, misuse and data leaks. It covers who can call the API, what they can do, and how the traffic and data are protected.
Authenticating every request and authorizing every record is the most important pair. Broken access control is the most common cause of API data exposure.
Use a platform that handles authentication and secure connections for you, then configure roles, validation rules and secrets yourself. With Base44, you describe your app in plain language and set the access rules that match your business.
Test before every launch and after any change to authentication, permissions or data. Add a regular review, such as quarterly, to catch drift and forgotten endpoints.
Authentication confirms who the caller is. Authorization decides what that caller is allowed to see or change.