How to get a Claude API key from Anthropic

Getting a Claude API key takes five minutes on Anthropic's developer console. You need an account, a phone check, a few credits and one click on "Create Key". The key gives you access to the Claude models at the official rate, billed on the volume actually processed. For writing, Claude is one of the most popular engines on the market, especially for the quality of its writing.

The process looks a lot like the one at other providers, with two specifics. Anthropic asks for an SMS check and runs on prepaid credits. The steps follow in order, with prices recorded in October 2026 and the difference you need to understand between the API and the Claude Pro subscription.

01Key takeaways

• The key is created on Anthropic's developer console (platform.claude.com), a space separate from the claude.ai chat interface.
• Anthropic gives new accounts small trial credits to test the API. After that, you top up the account with prepaid credits.
• The key is shown only once when you create it, so copy it straight to the right place.
• Three model families cover every budget. In the current 5.5 generation, Haiku costs $0.10/$0.50 per million tokens, Sonnet $2/$10 and Opus $4/$20, while the 4.x models stay on sale at $1/$5, $3/$15 and $5/$25, according to the price list of October 16, 2026.
• The Claude Pro subscription at $20 a month is a different product. It pays for the chat interface and gives no API access.

02Claude API and Claude Pro are two separate products

The most common confusion deserves to be cleared up first. Claude Pro, at $20 a month ($17 on annual billing), is the subscription for the claude.ai chat interface and includes no API access. The API key is tied to a developer console account instead and is billed by consumption, with no subscription.

To produce content with tools, the key is what you need. It's what lets you switch to AI without a subscription, paying for each task at its list price instead of through a plan or resold credits. The two can coexist, since they answer different needs and are billed separately.

A simple check tells you where you are. If you're on claude.ai, you're on the chat side. If the address shows the console and talks about keys, credits and limits, you're in the right place for the steps that follow.

03Step 1. Create the account on the developer console

Go to platform.claude.com, Anthropic's developer console (the old address console.anthropic.com leads there too). Sign-up accepts an email address or a Google account. If you already use claude.ai, you can use the same login. The console stays a separate space with its own billing.

Anthropic asks for a phone check when you create the account. A code arrives by SMS and the whole thing takes thirty seconds. It's a standard anti-abuse measure among AI providers. The number isn't used for anything else or ever shown publicly.

04Step 2. Credits and the cap

The Claude API runs on prepayment. You load credits and your usage draws them down. New accounts receive small trial credits so you can test without a card. For real use, a first top-up of around $5 easily covers several months of writing, as the figures on per-use cost show.

Prepaid credits have a reassuring virtue, because spending can't exceed what you've loaded by design. Back this up with the console's limit settings. They let you cap usage per workspace and avoid any surprise, even when a script runs out of control.

Just avoid the opposite reflex of loading too much at once to feel safe. Start small, watch your usage for a month and adjust afterward. Credits don't expire quickly, but money sitting idle does nothing for you, while a top-up takes one minute when the day comes.

05Step 3. Generate the key

1. In the console, open the API Keys section from the settings.
2. Click "Create Key" and name the key after its use. "writing-tool" beats "test-2".
3. Copy the key shown, which starts with sk-ant-. It will never be displayed in full again.
4. Paste it straight into the tool it's meant for, then close the tab.

If you lose the key or close the window too fast, delete it and create another one. The operation is free and instant. A regenerated key is always better than one copied back from a file lying around on your computer, so make that swap your default habit.

06Step 4. Secure it right away

An API key commits your credits, so treat it like a password. Don't publish it anywhere, only hand it to tools that store it in the browser or encrypted and revoke it at the slightest doubt. The security rules for API keys fit on one page and apply to every provider. They take ten minutes to read and spare you some nasty surprises.

The console also helps you keep things in order. Create one key per tool with a clear name instead of a single key copied everywhere. The day a use ends or a doubt comes up, you cut off that key without touching the rest of your production.

07What the Claude API costs

The official price list of October 16, 2026 is shown per million tokens. Input is your instruction plus the context you supply. Output is the generated text. Output is billed at a higher rate, which is the rule at every provider.

Anthropic API rates per million tokens, official price list of October 16, 2026

Model	Input	Output
Claude Fable 5.1	$10	$50
Claude Opus 5.5	$4	$20
Claude Sonnet 5.5	$2	$10
Claude Haiku 5.5 (prompts up to 100,000 tokens)	$0.10	$0.50
Claude Opus 4.8	$5	$25
Claude Sonnet 4.6	$3	$15
Claude Haiku 4.5	$1	$5

In practice, a 1,500-word article generated on Sonnet 4.6 costs less than five cents. On Haiku 4.5 it costs about a cent and a half. The 5.5 generation lowers those figures to under three cents on Sonnet 5.5 and about a seventh of a cent on Haiku 5.5. Two discounts apply on top. Batch processing halves prices. Repeated input also lets you cut the bill with caching, since it's served at a tenth of the rate. For content writing, Sonnet is the most common choice, while Opus is kept for jobs that demand the very best. As a benchmark, the $20 Claude Pro chat plan equals several hundred articles billed through the API. For tool-based production, the math is quick.

08Connect the key and get to work

The key works right away in any BYOK-compatible tool. At OpenTahr, paste it into the settings of a free account. Your Claude API key stays in your browser and never on our servers. The writing, audit and image tools then work with it, with no AI cost added. Mixing providers is good practice too, with Claude for polished writing and a light model from another provider for routine work.

To set up the other engines, the index of provider guides covers each console, from the spending cap to pasting the key. Once you've created the first key, the next ones take about three minutes each, because every console follows the same basic logic.

09Frequently asked questions

Is the Claude API free?

Not for long. The small trial credits on new accounts let you test. After that, usage is paid per token. If your priority is to try BYOK without a credit card, start with a free Gemini key instead. You can then come back to Claude once your need for writing quality becomes clearer.

What's the difference between claude.ai and the console?

claude.ai is the consumer chat interface, with its free tier and its Pro subscription. The console is the developer space for keys, credits, invoices and limits. The two share the login but not the billing. Paying for Claude Pro doesn't credit the API. Likewise, loading the API doesn't give you Claude Pro.

Is the process the same at OpenAI?

Broadly yes, with different menu names and, depending on the region, pay-as-you-go billing rather than prepaid credits. The OpenAI walkthrough details each screen, spending cap included, so you can set up a second provider in a few minutes.

Which Claude model should I start with?

Start with Sonnet, in version 4.6 or the cheaper 5.5. It's the quality-to-price balance that suits web writing, emails and summaries alike. Move to Haiku when volume becomes the main criterion and to Opus when a text calls for the top tier. The best habit is still to test two models on a real task of your own. You can judge the difference in output in five minutes on your own text, which beats any comparison.

Transparency note. Prices and how the service works were recorded on October 16, 2026 from Anthropic's documentation and official pages (links below). The trial credit policy varies over time, so rely on what the console shows when you sign up. Anthropic doesn't pay us.

10Sources

1. Anthropic, official Claude model pricing (API, caching, batches)
2. Anthropic, Claude Pro and Max plans
3. Anthropic, Claude API pricing documentation (all models)